Week 4: Fox's Generalizations, Yellow Fever, Dengue Fever

What do you know about foxs generalizations In regards to the public?

-At the beginning of most epidemics, many people have underestimated severity

-considerable fear and anxiety has accompanied perception that the epidemic was gaining strength

-initial responses to fear and anxiety have included flight, denial, and scapegoating of alleged carriers of the disease that were notably foreigners

what do you know about foxs generalizations in relation to procedures put in place?

-Efforts to quarantine, those who may have the disease, and isolate, those who do have the disease, have usually been ineffective in limiting the spread of an epidemic

-after a period of denial or panic, rational policies have been established during each epidemic, almost always by a coalition of business and government leaders, with the support from prominent members of medical professions

what do you know about foxs generalizations in relation to shortages? What is an example?

-in most epidemics there have been shortages of physicians and nurses to treat be sick in the poor. Shortages of positions have almost always been met by providing incentives, usually money an future practice opportunities, to physicians of lower status, often from another city or a foreign country

-for example in Hungerford in 1885 there was an outbreak of typhoid fever. One physician was there for the whole population but they became ill and so Med students from the University of Toronto were offered positions to come in and help

what do you know about foxs generalizations in relation to endemics versus epidemics versus pandemics?

-Such endemic infectious diseases such as syphilis tuberculosis and typhoid have posed many of the same problems of fear denial and mobilization as epidemics and pandemics have

what do you know about foxs generalizations in relation to money?ex?

-Epidemics are always expensive. They have exacted heavy toll in direct costs such as treatment in public health measures, and indirect costs such as losses of productivity, especially of lifetime earnings period that burden has always been borne by government and philanthropy as well as by private individuals

-one way that this loss of money was combated after the SARS outbreak in 2003 was a vast inflow of concerts because concerts or one of the main things that bring tourists and therefore money into Toronto

what three different terms was yellow fever also known as and why was it also known as this?

-Saffron scourge, yellow Jack, black vomit fever

-it was called black vomit fever because this was a symptomatic cause of death. It speaks to what happened when people got the disease such as vomiting black and having a fever

-yellow Jack was often put on a flag and hung up to inform others that that community is currently infected. Yellow was also a form of symptomatic cause of death

what do you know about the yellow fever virus?

-It belongs to the family Flaviviridae which are characterized by having arthropod vectors such as mosquitoes and ticks

-Is of the genus Flavivirus such as YFV, Dengu fever, West Nile; Viruses can affect humans and or animals

What is a virus characterized by?

-It must be in a living host cell to grow and replicate otherwise it's just RNA in a protein coat

yellow fever infection is often described as a mosquito borne viral hepatitis. What does this tell us?

-The mosquito borne indicates that the illness is vectored by mosquitoes

-the word viral tells us it is a virus infection

-the fact that it is a form of hepatitis indicates that the liver is going to be a particularly affected body part

-it also tells us that there are going to be high levels of viremia as this is a requirement for insect vector borne diseases

what is viremia and what do you know about it?

-It is when the virus is carried in the blood and it is a requirement for insect vector borne diseases such as mosquitoes

what is the incubation period of yellow fever?

-Three to six days after infection. During this three to six days the virus remains silent

after the incubation period, what three different types of phases or things can the person proceed to?

-They can have no symptoms or they can enter the acute phase or the toxic phase

what do you know about the acute phase of yellow fever?

-The individual will develop a fever, headache, muscle pain, nausea and vomiting; This persists for three to four days-85% of these people will improve and 15% will go on to the toxic phase

what do you know about the toxic phase of yellow fever?

-Compromised liver and kidney function occurs. The liver becomes unable to produce essential blood clotting factors leading to bleeding from the mouth nose eyes stomach and thus blood in stool and vomit. People develop the characteristic black coffee ground vomit. The liver also starts overproducing bilirubin which is a yellow pigment produced from the breakdown of red blood cells and thus people appeared jaundice, hence the yellow part of yellow fever

-half of these people will die within 10 to 14 days

what do you know about the yellow fever distribution historically?

what do you know about yellow fever distribution currently?

-Tropical slash subtropic areas such as Africa, central South and North America, Europe, and the Caribbean islands. It has never been reported in Asia - then

-Tropical areas of Africa and the Americas as well as several Caribbean islands - now

which part of the earth is the Tropic band?

-The pink part

how many people get yellow fever a year and how many people die from it?

-It is estimated that 200,000 cases occur a year with 30,000 of those people dying

what does the yellow fever endemic zones in Africa look like?

What does the yellow fever endemic zones in South America look like?

Who are the usual hosts of the yellow fever?

-Humans and other primates such as monkeys and apes

what are the two main forms of yellow fever transmission?

-Moves from host to host via a biting mosquito which is horizontal transmission

-mosquito able to pass infection by infected eggs to offspring which is vertical transmission

-mosquito is the true reservoir ensuring virus survival from year to year

what are the three transmission cycles we looked at in relation to yellow fever?

-Sylvatic, intermediate, and urban

what is sylvatic yellow fever transmission cycle?

-It is also known as jungle yellow fever transmission cycle. It does not involve humans. It plays out in nature where we may not even realize it is infecting other primates like monkeys

what is intermediate yellow fever transmission cycle?

-This occurs in the transitional zones. It occurs in the zones where other primates like monkeys and apes come into contact with humans. Thus the yellow fever virus can move between nonhuman primates and humans

what is urban yellow fever transmission cycle?

-No monkeys are involved. Human and urban mosquito; Aided by high population densities. This shows that mosquitoes can adapt very well to different environmental settings

to avoid an epidemic at least 80% of populations must have immunity to the yellow fever virus. How can this occur?

-This can occur via prior exposure, vaccination programs, spraying to kill mosquitoes during epidemic allows for vaccination of group at risk but must recognize early cases and they cannot be confused with other illnesses like malaria

what do you know about maintaining control of yellow fever in relation to Costa Rica?

-Costa Rica requires a person traveling to Costa Rica from certain countries in South America and sub Sahara Africa to have confirmed yellow fever vaccination

what do you know about some current problems in regards to the yellow fever epidemic?

-We are seeing a rise in yellow fever epidemics. Mosquito habitats and populations are expanding as humans continue to urbanize nature and deforest nature. We are also seeing that there are many susceptible unvaccinated population since worldwide vaccination programs are very very expensive

What do you know about the history of identifying mosquitoes as the transmission vectors of yellow fever?

-As early as the 1980s, Carlos J Finlay who was born in Cuba in 1833 and died in 1915, physician in Havana, insisted mosquitoes were critical in yellow fever transmission

-this was debated but noted many years later by Walter Reed who was a major in EU S Army Medical corps. In 1901, him and his team finally and firmly concluded it was mosquitoes that played a role in the spread of yellow fever. Walter Reed medical centre is now something in the USA

why was the US military interested in determining how yellow fever spread?

-This has to do with the Panama Canal. Construction of this began in 1880 and was completed in 1914. Where this was being built had a high exposure to mosquitoes and the thousands of workers died due to yellow fever and malaria and not great working conditions.

-The intention of the canal was to join the Pacific and Atlantic oceans so that merchants and navies could cross without having to go all the way around South America. It was a 77 kilometer canal instead of a multiple day adventure. Thus USA sent their medical corps to try to figure this out and save the workers so that they could save time in transportation

What are the three yellow fever milestones we focused on?

-In 1901 there was a transmission via mosquito vector

-in 1927 yellow fever virus was isolated using fine filters and microscopy

-in 1936 the vaccination became a thing for this

what do you know about Aedes aegypti?

-this is the specific type of mosquito that spreads yellow fever and dengue a fever

-typically lives in wet environments and favors rodents

-highly adaptable as an urban mosquito- synanthropic and anthropophilic

-Prefer small bodies of clean still water for breeding so containers and collection sites like water tanks tin cans vases tires etc are good breeding rounds

-not a strong flyer, can only fly a few 100 meters, and thus they benefit from crowded situations. They are daytime biters especially during dawn and dusk

-seasonality of rainfall- first heavy rain revived dormant eggs thus they can survive seasonal droughts

I mentioned that the type of mosquito and the last question is synanthropic and anthropophilic. what do these mean?

-The first one means that the species is settled in and benefits in being in close association with human populations

-the second one means that if you were to present the mosquito with many different bodies for blood meals such as humans dogs monkeys etc, they prefer to bite human bodies but overall prefer primates over any other group

what is the perfect urban mosquito life?

-Warm temperature for more blood meals, clean water for breeding, and no predators such as goldfish and eels, and humans for biting

what do you know about mosquito control measures?

-There is direct control measures such as larvicide slash insecticide, eliminate slash oil standing water, the top down or community based measures

-if you cannot prevent them from being present, you can reduce human contact: screaming buildings, mosquito repellent, protective clothing

what do you know about how dominicans view disease and health and medicine?

-They are sophisticated borders of information from western bio medical public health messages, indigenous African folk traditions, and pan Caribbean survival strategies. This is due to their political history

what do you know about some of the differences between the original research done on the ethno ecology dengu fever and the current research?

-The past one was more of a western view and failed to take into account how the Dominican people themselves viewed medicine and healing and what they felt was the right pathway to take in those situations

-the new one also puts a strong focus on gender roles and how that contributed to the spread of dengue fever whereas the original one paid no attention to how gender roles could have impacted the spread

what do you know about ethno ecology of dengue fever?

-Analysis of indigenous perceptions and linguistic categories that frame a biocultural E described environment. This includes political history of a group in this article- specifically dominicans living in barrio villa Francisca in Santo dominico

what is mala unioń?

-Result of historical and contemporary failure of political and administrative authorities to uphold their responsibilities. lack of political will is one of the reasons that community based intervention programs failed

what do you know about the vectors of Dengue fever?

-mosquito Anopheles, breeds primarily in large bodies of water. Their full name is Aedes aegypti. they are the vector for dengue fever transmission and are concentrated in periurban domestic settings, often breeding in artificially created water receptive

how is gender roles related to dengue fever?

-Since the mosquito liked to hang out in bodies of water, and women we're often the ones around the water, they had a big part in spread

-vessels of water were used for cooking for flowers for water purifying and for cleaning which were all women's jobs. The only male job of water was a 55 gallon tank that some people had directly outside their living quarters

-since the majority of the water sources were women's responsibility, the government suggestions to decrease tango fever in relation to how to handle the water was directed to women and therefore the outdoor storage is that were the men's responsibility remained uncovered and untaken care of in a dengue fever spread way

what is dengue fever?

-It has been recognized for more than 200 years period it is a non fatal infection causing incapacitating bone pain and debilitation. it is still an increasing concern because it can lead to dengue hemorrhagic fever and dengue shock syndrome, known to cause severe hemorrhage is an shock and even death

what do you know about ethnomedical and biomedical models coexisting in relation to dengue fever?

-In Dengue research, ethno medical and biomedical models coexist but rarely combine. Ethnomedical analysis describes indigenous perceptions of illness causation, diagnosis, treatment ecological studies describes formally quantitable variables such as energy expenditure, quantity of water use, and vector density IE creating and maintaining an artificial portrait of ill health in which interaction of human and nonhuman is not presented as interdependent

what do you know about how common Dengue fever is in barrio villa francisa?

-It is so common in the Dominican Republic that people accept this part of life. The report it is an endemic with antibody rates of about 70% in children younger than ten years of age

-tidwell did some research in barrio villa francisa and neighboring villages and reported they were able to catch 134 female mosquitoes in 10 minutes in one house. In the 1970s, about 30 to 40% of houses contained that specific mosquito larvae and it is assumed that that percent has only increased with time

what do you know about Santo dominico population in terms of how it connected to dengue fever?

-Between 1950 and 1960, the population increased sixfold. By 1989, capital city had population of 2.25 million people. This rapid population increase was not matched by a concomitant increase in public service infrastructure such as expansion in water and sanitation systems or housing. therefore it spread more quickly because the standards of living got even worse and people were in closer contact with more feces and such

-16% of these urban Dominican families were headed by women

barrio villa francisa is an economically marginal neighborhood, neither squatter settlement new or middle class. what do you know about this and what do you know about how their infrastructure changed and why?

-it occupies in older corner of the capital villa Francisa

-it is an older, urban neighborhood of Santo dominico that consists of a single family dwelling, multi similarities, apartment houses, and patios. Often a single patio might have 20 to 40 families in small single rooms, sharing a single common latrine and water tap. Water taps are often run by electricity which is often turned off for two to three hour increments multiple times a day

-in 1988, president balaguer turned single family houses into multi homes. Some of the houses that were torn down and became multi houses were not necessarily given to those whose the original house was

what do you know about the methods of gathering information in the original study done on dengue fever in the Dominican?

-Objective of the original study was to conduct an ethnography of dengue fever, describe household ecology of the specific mosquito, identify constraints to the community- participation activities, and proposed feasible means to overcome constraints. This was done over nine months in 1989 and 1990

-many people responded to the anthropologist desire for informants but at the end of the day nine individuals were selected as key informants based on their knowledge of the history and population of the community

what do you know about an indigenous typology of water in terms of an ethnological analysis of dengue control?

-Most villa Franciscans use tap water for washing. However this was not good water by any means and therefore they use water from a standpipe or public water source for cooking and drinking. They only ever use purified water for health crisis is an important visitors even though they knew that this was truly the only water source available to them that was clean and fully healthy

what do you know about the knowledge that people in the Dominican had about dengue fever?

-Mosquitoes, water, and gusarapos which was their larvae or all associated in the ethnomedical model of dengue fever

-85% of people questioned associated mosquitoes with the transmission of dengue fever, 65% incorporated the concept of vector in their answer

-they knew it was transmitted by contact with larvae by injection by mosquitoes and through microbes

-60% of those questioned incorrectly thought mosquitoes bred in garbage and plants

-they knew certain people were more at risk. They also knew they needed to keep themselves clean to decrease the spread an likelihood of them getting it. They tried to control the spread and tried to cover their water

what is gripe?

-Gastrointestinal distress

Note: 5% of households in the sample paid someone to carry their water for them. This was often done if it was a fully female household and they were not strong enough or did not have enough time to do so

among villa franciscans, the average household size was what and how much water did each person need a day?

-the average household size was nine people and each person needs about 18 to 20 liters of water a day