Preventive Medicine in Humanitarian Emergencies

Transcription

1 2 MODULE 2 Preventive Medicine in Humanitarian Emergencies Dougas Lougee Sathyanarayanan Doraiswamy Ángea Gentie

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3 Preventive Medicine in Humanitarian Emergencies 2 Dougas A. Lougee, MD, MPH Sathyanarayanan Doraiswamy Dr. Ángea Gentie INTRODUCTION Why is Preventive Medicine and Pubic Heath Important after a Disaster? In a post-disaster scenario, heath workers are faced with many chaenges. For exampe, they may be concerned for the safety and we-being of their own famiies as we as the heath and we-being of their patients. Most wi have an innate desire to hep their community. Depending on the specific scenario, pediatricians may have to use skis that are beyond those of everyday practice, such as trauma care in the immediate aftermath of an earthquake. However, in any disaster situation, preventive medicine and pubic heath techniques are ikey to be most usefu aspects for overa community recovery. At its core, preventive medicine focuses on the use of popuation heath data and pubic heath strategies to improve the heath of an entire community. After a disaster, the day-to-day pubic heath infrastructure is suddeny disrupted. Much ike the autonomic nervous system, which maintains bodiy functions without conscious effort, this infrastructure works day and night to maintain community heath without being appreciated. Foowing a sudden disruption of the pubic heath services, the community faces potentiay catastrophic consequences of not knowing where to go to seek preventive and treatment services. The coapse of pubic heath systems puts communities at high risk of communicabe diseases which are associated with high morbidity and mortaity. In these situations, reestabishing the pubic heath infrastructure shoud have a higher priority than caring for individua patients.

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5 SECTION I / GATHERING AND USING DATA GATHERING AND USING POPULATION DATA OBJECTIVES Recognize the difference between standard cinica practice and preventive medicine. Reca the ways in which, after a disaster, pubic heath measures have a higher priority than caring for individua patients. Describe and appy popuation evauation toos such as rates and underying causes of disease present in a given community affected by a disaster. Preventive Medicine: A Pubic Heath Mindset In cinica practice, physicians spend most of their time diagnosing and treating patients one at a time. Most heath care is focused on caring for the patient. Preventive medicine, rather than trying to hep the individua patient, focuses on the underying causes of iness in society and empoys pubic heath techniques to address these probems at the popuation eve (Box 1). The CASE After an earthquake, a food poisoning outbreak was detected in a cub used as a sheter. An epidemioogist conducted the investigation. On his arriva, Dr. HN was informed that on the previous night a the affected persons had eaten at the cub. The investigation focused on the meas served the previous evening. Seventy-five of the 80 persons who had been present were asked about symptoms, incuding when they were first noticed (date and time of their onset).there were 46 persons with symptoms of gastroenteritis. 1. Can the situation be considered epidemic? In a cases, the symptoms, primariy nausea, vomiting, diarrhea, and abdomina pain, had an acute onset. None of the persons had fever. They a recovered spontaneousy in a 24- to 30-hour period. Approximatey 20% of the persons who had dinner at the cub sought medica care. Sampes for feca cuture were not obtained. 2. List the diseases that shoud be considered in the differentia diagnosis when an outbreak of acute gastroenteritis occurs. Dinner had been prepared simutaneousy by severa peope and had been served in the cub yard between 6 p.m. and 11 p.m. The meas had been paced on tabes and eaten during a period of severa hours. A 75 interviewed persons were asked about the time of onset of symptoms, and the meas and beverages they had. A tabe was created using these data (see the Appendix on page 28). The exact time of food ingestion coud be estabished in ony about haf of the cases. (Continues on page 9)

6 6 SECTION 1 / GATHERING AND USING DATA BOX 1. Characteristics of preventive medicine It is based on pubic heath It deas primariy with the heath of groups, not of individuas It uses mathematica data It investigates the underying causes of disease in the community preventive medicine patient is considered a group of peope, a popuation, or an entire community with sub-groups within that community. The first step the trangroup, mutipied by an even number depicting the popuation at risk (Box 2). Rates faciitate the comparison between the reaity of one community and that of others. They aso hep assess through time the success of interventions in a given popuation. Determining rates is a ski that many cinicians do not use on a daiy basis, but it is critica to understanding heath probems in a community. Without this data, scarce resources wi not be used ration- Rates faciitate the comparison between the reaity of one community and that of others. They aso hep assess through time the success of interventions in a given popuation. sition from cinica practice to preventi ve medicine is to understand your patient.in cinica practice, patients come for consutation with the cinician one by one. Vita signs are determined, and the history, physica examination, and perhaps aboratory tests are used to arrive at a diagnosis and rationa treatment pan. In preventive medicine, the patient is not an individua but a group of peope: an entire community. Arriving at an accurate community heath diagnosis invoves taking vita signs ; however, in this case, those vita signs are mathematica data rates of disease within the community and sub-groups within it. Use of Rates: Vita Signs of a Community Rates are a fraction representing numbers of cases of specific conditions over the number of peope in a specific popuation BOX 2. The patient of preventive medicine Groups, not individua patients Vita signs = Rates of disease Rates = persons x even number persons at risk Even number: represents the size of the popuation (1,000, 10,000 or 100,000) ay for the good of the community. This is particuary critica in post-disaster scenarios where resources, such as time, are more constrained than usua. To obtain rates, one must have both a numerator and a denominator. The numerator is the number of cases of a specific type of probem, and the denominator is the number of peope in the community who are at risk for the probem. The resuting number can be reported as a fraction, a percent, or a rate. A of these convey usefu informa-

7 SECTION 1 / GATHERING AND USING DATA 7 tion and can be converted from one to another. Using a rate is the way that most pubic heath practitioners speak to each other and is probaby the most usefu (Box 3 and 4). BOX 3. Rates Exampe: Chidren younger than 5 years of age with diarrhea Town A: Town B: 304 cases of diarrhea 1054 cases of diarrhea Which town has more probems with diarrhea? BOX 4. Rates: a numerator and a denominator Town A: 1597 chidren <5 years of age Rate: 304 X 10,000 = Town B: 12,818 chidren <5 years of age Rate: 1054 X 10,000 = ,818 Rates of diarrhea per 10,000 chidren younger than 5 years The vaue of a rate is dependent on the quaity of the data that go into its creation. For accurate numerators, cases must be defined ceary so that a busy cinician can easiy categorize probems. For exampe, a typica case definition woud be 3 or more watery stoos for a diarrhea case. Consistency in defining cases is key to ensuring the comparabiity of rates from different areas or foowing them over time. Equay important to determining accurate numerators are accurate and descriptive denominators. For this, basic demographic information is needed, such as the tota number of peope affected in the community and the popuation structure, incuding gender breakdown and number of peope in specific age groups. In a disaster scenario, the simpest way of subdividing groups by age is to cassify them under 5 years, 5 to 15 years, and over 15 years. It might be usefu to subdivide this ast group into 15 to 60 and over 60. The most critica rates to foow after a disaster are mortaity (death) rates. The daiy crude mortaity rate (CMR) is determined by taking the tota number of deaths in a popuation (community), dividing it by the tota number of peope in that popuation, and mutipying that number by 10,000 (Box 5). For exampe, if a community has a popuation of 15,955 and it experiences 49 deaths in 7 days, the CMR wi be 49 / 15,955 x 10,000 = 30.7 deaths per 10,000 peope in one week. To arrive at the daiy CMR, which is the internationa standard for gauging disaster severity and effectiveness of response, divide this number by 7 to get a daiy CMR of 4.4 deaths per 10,000 peope per day. The mortaity rate of chidren under 5 years, i.e. the number of deaths in chidren In a disaster scenario, the simpest way of subdividing groups by age is to cassify them under 5 years, 5-15 years and over 15 years. It might be usefu to subdivide this ast group into 15 to 60 and over 60.

8 8 SECTION 1 / GATHERING AND USING DATA Attack rates are incidence rates; i.e., they refect the number of new cases in a given popuation. BOX 5. Crude mortaity rate (CMR) Tota number of deaths in a group X 10,000 Tota number of persons in this group Expressed as deaths per 10,000 persons per day. The objective is <1/10,000/day younger than 5 years, is another important measure to assess the severity of a disaster and the capacity for response. It is important not ony because it shows the effects of the disaster on chidren, but aso because chidren are the most vunerabe members of society. This age group is usuay caed the sentine popuation, because changes wi become evident sooner than in other age segments. Heath-care workers shoud worry when the mortaity rate reaches 2 deaths/10,000 chidren age <5/day.The situation is considered severe when this rate mounts to 4 deaths/10,000 chidren age <5/day. Attack rates are aso usuay utiized during disaster situations. These rates express the reation between the number of newy diseased persons (cases) and the tota popuation at risk. Attack rates are incidence rates, i.e., they refect the number of new cases in a given popuation. On the other hand, prevaence rates measure the proportion of cases of different diseases in a given popuation. They express the specific weight of a given disease with reation to the aggregate of a diseases, and aow estabishing priorities in the management of diseases and the use of human resources. However, in contrast to incidence rates, prevaence rates do not refect the risk of an epidemic.

9 SECTION II / EVALUATION OF THE NEEDS DURING AN EMERGENC POPULATION HEALTH EVALUATIONS INCLUDING EMERGENC NEEDS ASSESSMENTS OBJECTIVES Reca major components of a popuation evauation: demographics, predisaster heath conditions, an emergency needs assessment, heath-care system evauation, and estabishing a surveiance program. Compete the major components of an emergency needs assessment. Draft disaster response pans using community resources (transportation, communication, security). CASE. (cont.) 3. How does the information on the incubation period (in addition to the cinica data) contribute to the differentia diagnosis of the disease? 4. Identify the vehice or vehices of the infection. (Continues on page 16) Popuation Evauation Pediatricians can faciitate post-disaster recovery in their communities by heping to assess oca popuation conditions. It is important to obtain as much hard data as possibe do not depend on specuation. Too often, disaster reief efforts are hindered and resources squandered by we intentioned peope acting without the background of sound epidemioogica data. Box 6 describes the components of a popuation evauation. Demographic Data In a disaster, coecting data on popuation characteristics (number, age groups, ethnicity, gender) is critica. The crudest form of counting peope is by air. This is by far the east accurate way of assessing the scope of a disaster, but it may be a that is possi be in some situations. Visua estimates from the ground may be used as we to get a quick count of the affected popuation. More accurate method to assess the affected popuation and its structure is by

10 10 SECTION II / EVALUATION OF THE NEEDS DURING AN EMERGENC Without accurate demographic data, it wi be difficut to determine the true nature of what is happening in a community and scarce resources may be wasted. Whenever possibe, it is preferabe to cose the gaps between needs and resources by mobiizing oca resources immediatey instead of waiting for outside assistance. BOX 6. Popuation evauation Demographic data Measures of heath status prior to the disaster Evauation of the emergency needs Estabishment of a morbidity/mortaity surveiance system using standard samping techniques, such as systematic househod samping. The most accurate way to gather demographic information is to count a individuas and ist them by age group and sex. Vunerabe groups (such as chidren under 5 years and/or without a famiy, breastfeeding mothers, pregnant women, the edery, and the injured) need particuar BOX 7. Demographic data Affected popuation count (high priority) Visua estimation Samping Census Popuation structure: mae/femae and age segments (<5 years, 5-15 years, >15 years) Risk groups: young chidren, pregnant and actating women, edery and wounded peope attention and must be identified. Athough counting peope and groups may be tedious, this is a top priority (Box 7). Humanitarian agencies such as UNHCR, WFP, OCHA register beneficiaries so consider obtaining popuation denominators from such agencies. Without accurate demographic data, it wi be difficut to determine the true nature of what is happening in a commu nity, and scarce resources may be wasted. Pre-disaster Heath Conditions Baseine heath data may be obtained from oca heath authorities. Immunization records provide a good source of demographic data. Heath workers can provide basic information on what type of heath probems were present in the pre-disaster community as we as the areas that are most ikey to be affected, such as the most vunerabe househods. Pediatricians can maximize their disaster preparedness by being active in preparing community heath pans and taking the ead in heping with community disaster dris. The idea situation woud be for a pubic and private heath care workers to meet periodicay to discuss community heath probems and practice disaster dris. This woud increase their knowedge of the community and its heath probems, and woud aow for reationships to be buit between the pubic and private sector before a disaster strikes. Emergency Needs Assessment A needs assessment ooks at what a community acks as we as what resources and capacities it can use to address probems. The objective of a needs assessment

11 SECTION II / EVALUATION OF THE NEEDS DURING AN EMERGENC 11 is to identify gaps between current community needs and resources. Whenever possibe, it is preferabe to cose these gaps by mobiizing oca resources immediatey instead of waiting for outside assistance. Emergency needs assessments (aso caed rapid needs assessments) are focused on those needs that can ameiorate the greatest amount of morbidity in the community (Box 8). Security, transportation, and communication are aso key eements of an emergency community needs assessment; however, these components may fa outside BOX 8. Critica items in the evauation of the emergency needs Drinking water Nutritiona status Sheter Basic sanitation Loca environmenta conditions Pubic heath needs the traditiona heathcare ream. They wi be covered in greater detai under Conditions of other community resources at the end of this section. Water Water is critica to surviva and must aways be a top priority. The quantity of water is a higher priority than quaity in the immediate post-disaster scenario. Providing cean water wi do more to prevent the spread of disease than any other preventive medicine intervention. An estimates of water quantity needs ony for drinking varies from 3 to 4 iters/person/day. However, the water needs wi increase to 15 to 20 iters/person/day when cooking, ceaning, aundry, and persona hygiene are taken into account. The immediate identification of water sources, ways to protect these resources and methods to improve water quaity are top priorities. Water purification systems may eventuay be provided by reief agencies. If there are immediate concerns about the safety of the water, then it can be chorinated by adding 2 drops of beach (sodium hypochorite soution) per iter of water. Nutritiona status Nutritiona assessments take into account community needs as we as oca resources. Again data, not specuation, is needed. The recommendation for caoric needs in a dispaced popuation is 2,100 Kca/person per day. Other eements of the nutritiona needs assessment incude food avaiabiity, nutrition quaity incuding avaiabiity of adequate micro-nutrients, food security, distribution throughout the community, and cutura factors that affect nutrition. Common samping techniques for surveying chidren s nutritiona status (or other heath condition) incude random seection (simpe or systematic) or custer samping. Simpe random seection can be done if a the chidren can be identified, such as by immunization records or a Providing cean water wi do more to prevent disease spread than any other preventive medicine intervention.

12 12 SECTION II / EVALUATION OF THE NEEDS DURING AN EMERGENC camp census. They are assigned a number and then a random number tabe is used to seect those who wi be evauated for nutritiona status. Systematic random samping is done by checking every nth househod to get enough chidren for a representative sampe. This is usefu if the househods are reasonaby neaty ordered, such as ordered in rows of tents. The interva between each househod that is samped (n) is determined by the tota number of househods in the community divided by the number of househods you wish to sampe. For exampe, to check the nutritiona status of chidren in 450 househods out of a tota of 2,800 househods, you woud check every sixth househod (2,800 divided by 450). The first househod to be samped woud be determined by randomy seecting a number between I and 6. Survey teams woud then check the nutritiona status of chidren in every sixth househod, beginning with the randomy seected one. Custer samping is a statistica samping technique that is used for arge numbers of peope and is beyond the scope of this discussion. A pubic heath professiona with training in epidemioogy or a standard text on this subject coud be used to design a survey using custer technique. If random seection (simpe or systematic) is used, a sampe size of about 450 chidren is needed. If custer samping is used, the sampe size shoud be of about 900 chidren for an accurate popuation estimate. If the community size is sma enough, it is more accurate to simpy check a the chidren who are in the sentine popuation age range. It is important to bear in mind that the sampe size wi depend not ony on the popuation size but aso on the frequency of the phenomenon being investigated; i.e., the prevaence of this phenomenon in the community. Sheter For sheter, the WHO recommends 3.5 to 4 squared meters (m 2 ) per person as the absoute minima amount of foor space for a dispaced popuation. A rapid assessment of avaiabe remaining space wi identify any disparity between needs and capacity. Predisaster panning shoud emphasize the use of community spaces such as schoos, churches, and assemby has for emergency sheter. Basic sanitation Basic sanitation is aimed at preventing spread of communicabe diseases from indiscriminant defecation. Feces are a concentrated source of human pathogens and can ead to exposive outbreaks of diarrhea diseases. In a post-disaster scenario, effective contro of human waste is a top priority. One person can contaminate water used by thousands, and fies can spread feca materia to food suppies, rapidy creating hundreds or thousands of cases of food and waterborne iness. Loca environmenta conditions Conditions that affect community heath, such as smoke, chemica spis, foods, and-

13 SECTION II / EVALUATION OF THE NEEDS DURING AN EMERGENC 13 sides, coapsed buidings, terrain sopes, drainages, and insect vectors, are a important to assess during disaster situations. Heath needs The emergency assessment of heath needs is focused on mortaity rates and the chief causes of morbidity. Death is the most severe negative heath outcome and it must be tracked carefuy to understand what is happening in a community. To provide the most accurate information, mortaity data shoud be reported by age, sex, and cause of death. Morbidity data is aso of key importance for understanding community heath needs. This data is captured by using patient ogbooks or records that record age, sex and chief diagnosis of the patient. This data can be rapidy anayzed to gain an understanding of the chief heath threats to the community and used to pan the use of resources accordingy. Heathcare System Evauation Whie not a part of the traditiona emergency needs assessment, an evauation of community heath-care resources, incuding human resources, medica suppies, equipment, surgica capabiity, emergency department and primary care capacity and the condition of heath-care buidings, is aso an important part of the process foowing a disaster. From the preventive medicine standpoint, evauation of the avaiabiity of vaccines and the condition of the cod chain is extremey important. Evauation of the heath-care system requires pre-disaster knowedge of community resources. By joining with pubic heath officias and disaster panning committees, pediatricians and other oca physicians can be incuded in community heath-care worker rosters and wi earn where emergency medica suppies are stored. Organized pans for signaing an emergency and identifying a specific ocation to convene as a group woud ead to rapid mobiization of a heath-care workers in case of an emergency. Identifying additiona areas for handing surge capacity and the staffing of these additiona treatment areas is important. For exampe, with a pandemic infuenza outbreak, current heathcare faciities can become overwhemed. Identifying aternate care faciities in each community and regionay may be needed to meet demands. Predisaster panning by deegating responsibiities for assessing the condition of oca hospitas and cinics and determining avaiabe medica suppies wi avoid confusion and wasted efforts. Estabishing a System of Morbidity and Mortaity Surveiance After a disaster, it is critica that a heath-care workers, both private and pubic, join together to form an integrated and coordinated system that records and reports diseases. This is one of the most important roes of heath workers Organized pans for signaing an emergency and identifying a specific ocation to convene as a group woud ead to rapid mobiization of a heath-care workers in case of an emergency. Morbidity data is aso of key importance for understanding community heath needs.

14 14 SECTION II / EVALUATION OF THE NEEDS DURING AN EMERGENC who are engaged in a traditiona cinica consuting mode. To the cinician who is working ong hours trying to treat as many patients as possibe, gathering data may seem ike a waste of time, but it is crucia for panning disaster response. The idea situation woud be to have every heath worker record the age, sex, and diagnosis of each patient. This information shoud be coected and recorded in a systematic way and provided in a timey manner to pubic heath authorities so they can anayze it and rapidy respond to emerging heath threats. In a sophisticated heath-care system, eectronic medica records can greaty faciitate this data acquisition. Conditions of Other Community Resources Transportation and Communication Resources Transportation and communication are critica components of the disaster response strategy. Two-way communication systems such as radios, teephone, and Internet capabiity are critica for disseminating information, communicating among disaster workers, and panning outside hep. Use mass media for providing emergency instructions and heath education. The condition of roads, waterways, and anding strips/fieds is aso important for evacuating peope who are injured and receiving emergency aid. Motor vehices, fue sources, and boats may be important for rapidy estabishing a ogistica bridge into disaster-affected areas. Security Security is another need that is sometimes overooked by heath workers. Security may be needed to carry out the initia rapid emergency needs assessment or to maintain contro of victims seeking basic suppies or heath care access. Whie heath workers probaby wi not be caed upon to estabish security for disasteraffected popuations, they can faciitate protection from crime, ooting, and expotation by sharing information regarding crimina activity with security forces. Heath workers can aso provide security for unaccompanied minors by quicky taking contro of these chidren and keeping them safe from expoitation unti famiy reunification or another permanent soution can be achieved. Epidemic preparedness and outbreak response Given the eboa epidemic in West Africa, Hepatitis E outbreak in South Sudan, eow Fever in Sudan and the repeated choera and maaria outbreaks in various disaster situations and infuenza epidemics it is important to evauate whether a cinica faciity has an adequate epidemic preparedness pan. Is there a current pan for your faciity? How does this pan integrate with regiona pans. Have you considered contingency pans for yoursef or your coworkers in terms of providing chid care

15 SECTION II / EVALUATION OF THE NEEDS DURING AN EMERGENC 15 or famiy member care if they become sick. Additiona staffing needs may be arge. Is there a requirement for a your faciities heath-care workers to be vaccinated, and do those pans have a method in pace for those who refuse vaccination to prevent the spread of disease (noncinica work? Rues for wearing proper masks). Depending on the epidemic characteristics, certain popuations may be more affected than others, or there may be vast numbers of midy infected patients with few critica patients or an outbreak with many critica patients. Estabishing triage systems to sort these patients, a daiy surveiance of the types of these patients and degree of iness, as we as avaiabe hospita beds, wi hep shape ongoing pans. The resources needed for each or these situations wi vary, but panning ahead of time, such as adequate numbers of ventiators, antibiotics, anti-maarias, intravenous fuids, safe bood masks, vaccines, anti-viras shoud be addressed. Finay, estabishing aternate care guideines can provide a framework for deaing with a potentiay arge number or patients in a system that may become quicky overwhemed. Resource aocation, ethica considerations and the ega channes to enact these aternate care guideines shoud ideay be speed out a priori.

16 SECTION III / INTERVENTION PRIORITIES POST-DISASTER INTERVENTION PRIORITIES Feca ora transmission has the greatest potentia for rapid spread of infection through a dispaced popuation, particuary if the water suppy becomes contaminated. OBJECTIVES Estabish emergency intervention priorities foowing a disaster. Describe how the modes of disease transmission affect the intervention priorities after a disaster. CASE (cont.) 5. Determine the future investigations that shoud be carried out. 6. What contro measures woud you impement? Modes of Disease Transmission Post-disaster iving conditions frequenty enhance the transmission of infectious diseases. Understanding how these conditions pose heath threats wi hep set priorities for pubic heath interventions. The most common modes of transmission after a disaster are feca-ora, respiratory, and vector borne. Feca-ora transmission can occur by having human waste enter into the water suppy by indiscriminant defecation or by fooding, by fies carrying feces on their feet to food sources, or from unwashed hands. Feca-ora transmission has the greatest potentia for rapid spread of infection among a dispaced popuation, particuary if the water suppy becomes contaminated. The respiratory route is enhanced by the crowded conditions that frequenty foow a disaster. Aso, respiratory irritants such as smoke from open cooking fires may increase predisposition towards the spread of respiratory pathogens. Vector-borne inesses such as maaria and dengue frequenty increase foowing disasters, particuary foods or hurricanes because standing water increases mosquito breeding. Infections are usuay referred to when the notion of transmission is being discussed, because infection transmission is easier to prove objectivey. In contrast, the epidemioogic evidence of causaity in the transmission of noninfectious diseases is more difficut to demonstrate. An exampe is ung cancer associated with cigarette smoking. There are four modes of transmission of infectious diseases: contact, common source, airway transmission, and transmission by vectors. Contact This necessitates a connection between the host and the infectious agent that causes the disease. The contact can be direct,

17 SECTION III / INTERVENTION PRIORITIES 17 indirect or through dropets. Direct contact invoves person-to-person contact, as in the case of the feca-ora route, in which the microorganism contained in the feces of an infected person is transmitted, due to defective hygiene conditions, to another person, usuay another househod member. Exampes: hepatitis A, Samonea, Shigea. An additiona exampe is the contact with a Staphyococcus aureus infected wound. Indirect contact is through an inanimate object. Exampe: hepatitis B, due to the shared utiization by famiy members of objects such as tooth brushes. Finay, the contact through dropets is the person-toperson transmission through dropets emitted by the mouth or nostris. The ongest distance that dropets trave in the air is approximatey 3 yards. Exampes: meases, chickenpox, streptococca disease. Common Source A microorganism or a toxin can cause disease in one or severa persons from a common source that contains the infective agent. Exampe: gastroenteritis outbreaks resuting from contaminated food (ice cream, mushroom sauce) (Box 9). Transmission through the Air Microorganisms can trave more than 3 yards in the air from the source of infection. Traveing micropartices usuay resut from the evaporation of drops emitted by the source of the disease. Exampes: tubercuosis (through the cough of a diseased person), psittacosis (from a diseased fow to a person), Q fever (from contaminated products; can trave severa mies), and Legionea (through air-conditioning systems). Water Food BOX 9. The most common sources for disease transmission Mosquitos and fies Bood products Intravenous administration practices Transmission by Vectors Transmission by vectors can be externa or interna. In the externa transmission, the vector carries the unmodified infective agent on its body. Exampe: fies carry Samonea acquired from contaminated feces and deposit the bacteria on food that is ater ingested by the host (human being or anima). In the interna transmission, the microorganism traves inside the body of the vector, where it may remain unatered (ersinia pestis is ingested and then eiminated unchanged) or may be modified, as in Pasmodium faciparum transmission by the mosquito. Recognize that transmission can occur by one or severa modes (Tabe 1). Pubic Heath Priorities The objective of post-disaster heath interventions is to minimize death and prevent excess disease. Another pubic heath priority is to faciitate community

18 18 SECTION III / INTERVENTION PRIORITIES TABLE 1. Most frequent diseases during disaster and their forms of transmission Transmission Bacteria Viruses Other Feca-ora Samonea Shigea Escherichia coi Vibrio Choera Hepatitis A and E Rotavirus Pinworms Giardia ambia Ascariasis Airway N. meningitides S. pyogenes S. pneumoniae Respiratory syncytia virus Varicea zoster Meases Infuenza Skin S. pyogenes S. aureus Varicea zoster Herpes simpex Lice Scabies Ringworm Hookworm Bood, urine, saiva and other body fuids Syphiis (T.Paidum), Gonococci (N. Gonorrhea), Chancroid (H.Ducreyi) Hepatitis B and C Human immunodeficiency (HIV) Cytomegaovirus Chamydia trachomatis Mosquitos and other vectors Maaria, Leishmania eow fever, eboa, other hemorrhagic fevers preparation for future disasters. Ideay, a interventions are guided by a thorough emergency needs assessment and ongoing evauation of the team s effectiveness during a disaster situation. Among the survivors of the immediate inciting event, the eading causes of morbidity in disasters typicay are diarrhea and acute respiratory infections Immediate pubic heath interventions incude the foowing priorities: Provide safe drinking water Contro human waste Protect food suppy Vector contro Provide adequate sheter Provide Safe Drinking Water Providing sufficient quantities of cean drinking water is usuay the highest priority of a disaster reief efforts. Effective water purification programs wi ikey have a greater impact on community death and disease rates than any other

19 SECTION III / INTERVENTION PRIORITIES 19 singe intervention. To be effective, drinking water programs must be accepted by the community, so factors such as taste and convenient access to the purified water source must be taken into account. For ong-term panning, water purification programs must be sustainabe by the community once the disaster is under contro. Simpe fied treatment of water may improve quaity and decrease waterborne infections. Covering and aowing sediments to sette wi improve the quaity and decrease amount of chorination needed to purify water. Sand fitration by aowing water to percoate through stones and sand contained in a 55 gaon barre wi aso improve quaity of water. Buk chorination, when avaiabe, is another way to provide cean water to arge numbers of peope. Reverse osmosis units, such as those used by miitary, can provide thousands of gaons of pure water but are expensive, require expertise to operate, and take many days to deiver to a community, costing vauabe time. The east effective means of ceaning water for consumption is reying on the individua users to do it themseves by boiing or adding chorine to the water. Boiing takes time and effort. Ceaning water by adding beach or chorine at the househod eve reies upon motivation, efficient distribution of ceansing products, and most important, a fair amount of education to do it correcty. Utiizing an effective distribution system is equay important as having cean water. No matter the quaity of water at the source, it must arrive to the end users in some fashion. Cean, covered storage tanks are a top priority as we as a means to transport the water to community members. Contro Human Waste It is best to use a famiy-centered approach to estabishing portabe avatories. Take into account the specia needs of chidren when panning for community sanitation programs. Chidren are more ikey to defecate indiscriminatey and may not use a portabe avatory that is inconvenienty ocated, frightening, or does not meet their physica needs. Soap and water for persona hygiene are a ower priority when compared with drinking water suppy and the eimination of feces. However, after drinking water requirements have been covered, it wi be important to provide soap and water for persona hygiene to prevent the spread of infectious diseases. A minimum of 7 iters of water per person daiy is needed for covering hygiene requirements. Protect Food Suppy Deveoping a pan for protecting the food suppy shoud occur in disaster preparedness. Securing community resources and safey storing and protecting emergency The east effective means of ceaning water for consumption is reying on the individua users to do it themseves by boiing or adding chorine to the water. Protecting food preparation from contamination is a high priority.

20 20 SECTION III / INTERVENTION PRIORITIES rations are important detais to work out in advance and shoud incude a key agencies invoved with disaster panning. Protecting food preparation from contamination is a high priority. Basic measures for preventing food-borne iness incude: Using drinking water for food preparation Strict hand washing by food handers Keeping food preparation areas and utensis as cean as possibe Contro of fies and other vectors Proper cooking, storage and serving techniques. Provide Adequate Sheter WHO recommends at east 4 square meters of foor space for each person in an emergency sheter. Sheters are more effective if they keep famiies and other traditiona community groups together and are cose to resources such as food, water, avatories, medica care, and transportation. When homes are destroyed, it is far better to ocate sheters as cose to or within the pre-existing community whenever possibe. Additionay, providing heath education information may be necessary to hep community members prepare and use food resources safey.

21 SECTION IV / SURVEILLANCE CCLE THE USE OF THE SURVEILLANCE CCLE TO GUIDE USE OF RESOURCES OBJETIVES Use the surveiance cyce to hep make rationa heath-care decisions. Understand the key roe that primary care doctors and pediatricians pay in the compiation of quaity information, whie simutaneousy attending individua patients. Use this information in an appropriate way for decision making. Surveiance Cyce: A Powerfu Pubic Heath Too After the emergency assessment is competed and disaster recovery operations have started, ongoing surveiance wi evauate emerging popuation needs. Surveiance is defined by the U.S. Centers for Disease Contro and Prevention (CDC) as...the ongoing, systematic coection, anaysis and interpretation of pubic heath data essentia to the panning, impementation and evauation of pubic heath practice, cosey integrated with the timey dissemination of these data to those who need to know. The fina ink is the appication of these data to preven- tion and contro. A surveiance system incudes a functiona capacity for data coection, anaysis and dissemination inked to pubic heath programs. The surveiance cyce essentiay consists of gathering data that are critica for monitoring ongoing heath needs, anayzing and interpreting that data in a timey fashion, providing feedback to those who need to know, and taking actions based on these data (Box 10). After an action is taken, the cyce is repeated to re-evauate the effectiveness of this action (Figure 1). The most important point of the surveiance cyce is making sure that data are used. Unused pubic heath data that sit gathering dust is a waste of resources. For this reason, there needs to be a cear ink between data gathered by cinicians doing BOX 10. Important data Deaths Severe morbidity or diseases that are frequent in the community Rapid detection of seected conditions or infections, such as choera cases, manutrition, maaria, and severe trauma Document spread of infections by coecting ist of affected person The most important point of the surveiance cyce is making sure that data are used.

22 22 SECTION IV / SURVEILLANCE CCLE FIGURE 1. Surveiance cyce rescue efforts to conducting popuation surveys. Their effectiveness wi argey depend on persona preparation and their integration into community pre-disaster panning strategies (Box 11). Coected data Anaysis BOX 11. The pediatricians roe in preventive medicine Dris shoud invove chidren as mock victims, and represent the ages and numbers that are representative of the popuation at arge. Action face-to-face consutation and poicy impementation based on that data. If busy cinicians fee that keeping a patient ogbook ony adds more work to their day and has no impact on patient heath, they wi quicky stop gathering the data. This is where a breakdown between cinica and pubic heath services frequenty prevents optima use of the surveiance cyce. Preventive medicine roes of pediatricians foowing a disaster in their community Pediatricians, whether in pubic or private service, can assist disaster recovery in their communities in many ways. These need not be imited to simpy seeing chidren in consutation; with adequate preparation, pediatricians and other physicians and nurses can fi many important roes, from assisting with search and Before a disaster: not imiting themseves to direct patient care Evauations after the disaster: - Nutritiona evauation - Chidren s requirements Coaboration in disease surveiance: - Design of surveiance systems keeping chidren in mind - Coaboration in the coection and anaysis of data Chidren form a arge proportion of the popuation and because chidren are one of the most vunerabe groups during a disaster, it makes sense to have pediatricians serve as eaders in disaster response and preparedness programs. Dris shoud invove chidren as mock victims, and shoud represent the ages and numbers representative of the popuation at arge. Advance panning for meeting chidren s specia nutritiona, psychoogica, and deveopmenta needs wi ikey happen ony if pediatricians are invoved in every aspect of disaster panning. By teaching other heath workers, such as nurses, genera practice doctors, and ay community heath workers, pediatricians can disseminate their knowedge of chidren s specia

23 SECTION IV / SURVEILLANCE CCLE 23 needs throughout the disaster response community. Pediatricians in private practice may need to go out of their way to meet with pubic heath, miitary, and other governmenta officias to offer their services in pre-disaster panning. Waiting to act ad hoc after a disaster strikes is a recipe for wasted effort and represents an inabiity to make a meaningfu impact on community recovery. Even if pediatricians work primariy in their traditiona capacity of cinica consutation, they may sti have a significant roe to pay in preventive medicine by making sure that a functioning surveiance cyce is in pace. Crucia points of the cyce woud incude estabishing an adequate patient ogbook or record that captures important disease data and stratifies data to specific age and sex groups. This is where the surveiance cyce begins, with cinicians seeing individua patients. If they do not capture this data, pubic heath decisions wi be based on specuation, not facts. Next, pediatricians can ensure that individua patient data are shared with pubic heath authorities in a timey fashion, which wi aow anaysis and quick response to rapidy emerging pubic heath needs. Pediatricians who hande their own preiminary data anaysis by reviewing patient ogbooks on a daiy basis and ooking at disease incidence data in terms of rates wi aow quicker and more effective interventions and recommendations for resource aocation. Finay, by deveoping and maintaining effective communication with pubic heath eaders, pediatricians can ensure that wise decisions are made regarding the care of chidren in their communities.

24 24 SUMMAR SUMMAR Pediatricians have much to offer their communities in disaster preparedness and response. Knowedge of chidren s medica needs and a natura tendency to be advocates for chidren are pediatricians greatest assets. After a disaster, basic pre ventive medicine and pubic heath is generay a higher priority than providing cinica consutation for individua patients, and this wi hep increase pediatricians abiity to effectivey respond to a disaster in their community. Good preventive medicine techniques invove thorough popuation evauation and needs assessments, and using these data to guide initia disaster response. Setting up a functiona surveiance system wi hep evauate the adequacy of disaster response interventions and wi aert cinicians and pubic heath officias to emerging threats to community heath. Gathering and using data to intervene at the community eve wi hep ensure the best possibe outcomes for entire communities when a disaster strikes.

25 SUGGESTED READING 25 SUGGESTED READING Brown V, Moren A, Paquet C. Rapid Heath Assessment of Refugee or Dispaced Popuations 2 nd ed. Epicentere Médecins Sans Frontières, Paris, Carrasco, P. Vaccines in Disaster Situations: Recommendations of the PAHO/WHO Specia Program for Vaccines and Immunizations. These recommendations can be found at the foowing Web site: (as of 15 June 2005). Chin J. Contro of Communicabe Diseases Manua, 17 th ed. American Pubic Heath Association, Washington DC, Hansen R K. Preventive Medicine in Humanitarian Emergencies. In: Miitary Medica Humanitarian Assistance Course Manua, pp.vi 2-20, Uniformed Services University of Heath Sciences, Bethesda MD, Noji E. ABC of Confict and Disaster: Pubic Heath in the Aftermath of Disasters. British Medica Journa; 330: Pan American Heath Organization. Vigiancia Epidemioógica Sanitaria en Situaciones de Desastre: Guia para e nive oca. Washington DC OPS/PAHO Redmond A. ABC of Confict and Disaster: Needs Assessments of Humanitarian Crises. British Medica Journa, 2005: United States Agency for Internationa Deveopment Office of Foreign Disaster Assistance. Fied Operations Guide, ed.3.0. Washington DC, Word Heath Organization. Handbook for Emergency Fied Operations, Geneva, Mandaakas A, Torjesen K, Oness K, ed. Heping the Chidren: A Practica Handbook for Compex Humanitarian Emergencies. Johnson and Johnson Pediatric Institute and Heath Frontiers, Kenyon, MN, 1999.

26 26 CASE RESOLUTION Case resoution 1. The situation described in the case presentation can be considered an epidemic, taking into account the number of cases observed in the cub, which woud not to be expected. It is important to remember that an epidemic is defined as an increase in the number of cases at a given time and in a given pace, as compared with those observed at the same time and pace in previous years. 2. Diseases that can be considered in the differentia diagnosis of an outbreak of acute gastroenteritis incude: Bacteria: Samonea typhi, Shigea, Staphyococcus aureus (toxin) Vira: Rotavirus 3. Incubation times associated with the different potentia etioogic agents vary. Therefore, the estimation of the time interva between food ingestion and the onset of symptoms may hep identify the probabe etioogy of this epidemic outbreak. 4. The ikey vehice is one of the foods ingested during dinner. 5. It woud be appropriate to cuture feca sampes from the individuas responsibe for the preparation and distribution of meas, as we as from the sites in which meas were prepared and stored. It woud aso be adequate to obtain sampes for cuture from meas served during dinner, if they have been stored or not yet eiminated. 6. Impement strict hygiene measures in the cub kitchen, and insist on carefu hand washing by the persons responsibe for the preparation of meas. If a carrier of one of the potentia etioogic agents of the described outbreak is identified, isoate the carrier unti the pathogen is eradicated.

27 MODULE REVIEW 27 MODULE REVIEW SECTION 1 GATHERING AND USING POPULATION DATA 1. How can preventive medicine be characterized? 2. How is a rate defined? What purposes can rates serve? 3. What is an epidemic? 4. What factors shoud be taken into account for the contro of an outbreak? SECTION II - EVALUATIONS OF THE NEEDS DURING AN EMERGENC 1. What are the principa factors based on which a popuation is evauated? 2. How are demographic data obtained? 3. What is the best source of data to determine the heath conditions of a popuation before a disaster? 4. What are the key factors for assessing requirements during an emergency? 5. How are heathcare resources evauated? SECTION III - POST-DISASTER INTERVENTION PRIORITIES 1. What are the primary modes of transmission of diseases? 2. What are the most frequent sources of disease transmission? 3. What disease conditions are frequent during a disaster? 4. What are the pubic heath priorities after a disaster? 5. What are the post-disaster circumstances in which immunization is recommended? SECTION IV - THE USE OF THE SURVEILLANCE CCLE TO GUIDE USE OF RESOURCES 1. What components of the surveiance cyce are crucia for its effective impementation? 2. What roe do pediatricians pay in preventive medicine?

28 28 APPENDIX Information for the case resoution: Time of symptom onset and food ingestion by the individuas who deveoped gastroenteritis No. Age Gender I Day Time Time of food ingestion Onset of symptoms Boied ham Purée Squash Jey White bread Whoe wheat bread Mik Water Cakes Chocoate ice-cream Fruit saad

29 29 APPENDIX Food eaten by the individuas who did not deveop gastroenteritis F: femae; M: mae; : yes; N: no No. Age Gender I Day Time Time of food ingestion Onset of symptoms Boied ham Purée Jey White bread Whoe wheat bread Mik Coffee Water Cakes Vania ice-cream Chocoate ice-cream Fruit saad

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