Tools and methods for zika prevention in Cachoeira, Bahia

Florence Tesha

March 20, 2017

Zika virus, which is mainly transmitted by Aedes aegypti and Aedes albopictusmosquitoes, has become a major health threat in Latin American countries, especially in Brazil. Zika has also been associated with microcephaly, an infant brain abnormality. This project aimed to investigate the various tools and methods employed by the rural health centers in Brazil to prevent zika. The results of the study show that education and house visits by community health workers are the main tools used by these health centers. Rural health centers are also not as equipped as urban centers in the fight against zika. As the virus evolves genetically and habitually, rural areas are at a high risk for future outbreaks.

Background on zika virus

Zika virus (ZIKV), which is a mosquito-borne flavivirus, was initially isolated from a rhesus monkey in the Zika forest in Uganda in 1947. ZIKV circulated in other parts of Africa and Southeast Asia for decades, leading to no serious adverse outcomes or reports of outbreaks (Bell 2016; 589). The ZIKV outbreak in Brazil began in early 2015 and the vast majority of outbreaks are happening in the areas affected with dengue and chikungunya (Bell 2016; 590). In December 2015, Brazil reported preliminary estimates of 440,000 to 1.3 million cases of zika infections (Mlakar, 2016: 1). The transmission of zika has crossed borders and is now reported in other territories in Latin Americas, Cape Verde and the Pacific Islands (Bell 2016; 589).

Although zika affects people of all ages and gender, attention is focused in preventing ZIKV infections in pregnant women because growing evidence suggests an association between maternal ZIKV infection and infant brain abnormalities such as microcephaly (Bell 2016; 588). Microcephaly is a birth defect whereby a baby is born with a small head or the head stops growing after birth. Microcephaly can develop developmental disabilities due to poor brain growth of the baby (Facts 2016). Severe microcephaly can be life threatening; however, milder forms of microcephaly can lead to a child developing seizures, vision problems and intellectual disabilities. The major concern about microcephaly is that there is no vaccine or treatment, and the problems associated with it are often lifelong (Zika 2016). Additionally, the other problems detected among fetuses and infants infected with ZIKV before birth are absent or poorly developed brain structures, defects of the eye, hearing deficits and impaired growth (Questions 2016).

According to the 2016 World Health Organization (WHO) report on the ZIKV situation in Brazil, between October 2015 and February 2016, there have been 5640 reported cases of microcephaly including 120 deaths. 583 out of 5640 cases of microcephaly are related to ZIKV (ZIKA 2016; 9). In addition, recent reports from the Ministry of Health of Brazil suggest that cases of microcephaly have increased by a factor of approximately 20 among newborns in the northeast region of the country where there are more cases of ZIKV infections, hence indicating a possible association between ZIKV infection in pregnancy and fetal brain malformations (Mlakar, 2016: 2).

This study aimed to investigate the various tools and methods used to prevent and control ZIKV infections in the community by the Center for Endemic Diseases (Centro de Endemias; also known as Policlínica) in Cachoeira town and a rural health center in Alecrim named USF Justiniano de Jesus. Both health centers are funded and operated by the SUS (Sistema Único de Saúde; Unified Health System), Brazil’s publicly funded health care system. The major objectives of the study were to (1) explore the various ways that the urban and rural health care centers in Cachoeira work with the community to provide education of preventative measures of zika, dengue and chikungunya; (2) examine the perception of the health workers on the effectiveness of the methods and tools used by their health centers and the government to control and prevent zika, dengue and chikungunya; and (3) investigate whether there is an increase in the number of women seeking contraceptives after the outbreak of zika due to the scientific assumptions that it may be related to microcephaly and brain anomalies in newborns.

Background of the study location

This study was conducted in Cachoeira, an inland town of Bahia- Brazil, on the Paraguaçu River. The town of Cachoeira is a growing commercial and industrial center. The majority of the population in Cachoeira is young people between the ages of 18 to 45 and there are more women than men. 51% of the area is considered the urban area and 49% is the rural area. The urban area is more densely populated than the rural area. In 2010, the life expectancy of Cachoeira was approximately 70.7 years (Souza, Andréa; lecture March 2016). Cachoeira provides all primary and basic health services for everyone through the Family Unit Program. Families with a poor/low income receive support from the program of Bolsa Família as long as they fulfill the required conditions. One of the health conditions required under Bolsa Família includes getting vaccination.

Cachoeira is one among the many places in Brazil affected by zika infections with a few cases of microcephaly. I specifically chose to do this project in Cachoeira because it is less populated compared to big cities like Salvador, and thus there are more opportunities to interact with the health care workers since the hospitals are not always busy or full of people. The SIT, Salvador program’s relationship with the Alecrim health center also helped me to establish initial contact with the clinic and thus I had great support from the health care workers. Through the same network of people, I was introduced to the Centre of Endemic Diseases in Cachoeira, which became my second point of contact.

According to the data records of zika at the office of Secretary of Health in Cachoeira, zika cases peaked around the months of June to July 2015, but have been decreasing significantly ever since as can be seen in Figure 1. However, the number of cases reported has begun to increase in the month of March 2016.

The significant decrease in the number of zika cases from the months of July to August 2015 could be due to factors such as (1) weather changes, which affect the natural habitats of the mosquitoes; (2) intense and aggressive preventative measures that began to be implemented; or (3) changes in people’s behavior in trash management and proper maintenance of the environment. If the main factor for the decrease was weather patterns, then the number of zika cases reported is expected to rise significantly beginning April 2016 to July 2016, despite the preventative measures in place. If the number of zika cases continues to drop or rises slightly, then the sharp decrease would suggest successful implementation of the preventative measures against zika infections.

Figure 1. The number of zika reported cases in Cachoeira Municipal from April 2015 to March 2016 is shown.


All the data in this project was collected through questionnaires and informal interviews using the local language Portuguese. A total of 30 questionnaires were distributed. All the questionnaires were returned except 1 in Alecrim, and thus a total of 29 questionnaires were returned. The questionnaires used are reported in the appendices.

Participants and Selection Process

The main participants of this project were health care workers because they are the one’s responsible for organizing and/or conducting and implementing any events/training/programs of infectious disease prevention in the community. One of the secondary goals of this project is to evaluate the workers’ knowledge and perception of zika and the current zika related programs.

The Alecrim health center and the Center for Endemic Diseases in Cachoeira serve many people and thus the health workers have accumulated experience with community related programs. In addition, most of these workers have been working with the community to control and prevent dengue and chikungunya, which are also spread by Aedes aegypti.

All the participants were selected randomly through the connections of personal contacts. Some of the questionnaires stayed with the clinic’s receptionist and any health worker who wanted to participate in the project could take a questionnaire and return it to the receptionist. I collected the filled in questionnaires from the receptionist and individuals, depending on their preference.

Results and Discussion

The total number of health care workers who responded to the questionnaires was 29, with 24 females and 5 males. 78% of the respondents were between the ages of 30 to 49 years. Only 9% were between the age of 18 to 39 years and 13% were above 49 years old. Among the 29 participants, 18 had worked in their current position for more than 5 years, while 11 had experience of less than 5 years.

Knowledge of Zika

The health care workers are one of the primary sources of information for the community about zika and other related infections/diseases. The results of this study show that less than 50% of the health care workers had knowledge of zika above the scale of 5 (1=little/no knowledge, 10=fully knowledgeable). Therefore, more than half of the health care workers do not fully understand the history, causes, effects and prevention methods of zika.

Zika training among health care workers

51% of the health care workers received some form of training or informational session on zika organized by the Municipal Secretary of Health and conducted by medical doctors and nurses. All 29 respondents said that they would like to receive training and/or educational sessions about zika, dengue and chikungunya. This shows that there is demand for training from the health care workers.

Among those that had received training, 78% rated the usefulness of the training they received a 5 on a scale of 1 to 10, 1 being not useful at all and 10 being very useful. These data show that although most of the health care workers received some form of training or educational session about zika, the training was not very informative and effective in preparing them to take the front line in its prevention in the communities.

These results suggest that education and training of health care workers should be made a priority for zika infection prevention. For successful prevention programs, the health care workers need to be fully knowledgeable on the subject so that they can in turn be informants to the community.

Zika Perceptions among the health care workers

Since the outbreak of zika in Brazil, assumptions about the disease have proliferated. Although much research remains to be done concerning zika, preventative measures have already been established and implemented. Interestingly, one of the factors that affect prevention efforts is the perception of the danger or negative effects caused by infection. Thus, in order to evaluate how serious the preventative measures are being taken, one has to evaluate the perception of zika’s effects. Data collected through the questionnaires and interviews indicate that the majority of the health care workers believe zika is a dangerous disease. On a scale of 1 to 10, 10 being very dangerous, 18 out of the 29 respondents rated zika a 10, while none of the respondents rated it below 8. These results may suggest that preventative measures are being taken as recommended because of the perception of zika as a very dangerous disease.

Zika, Microcephaly and Contraception Use

90% of the health care workers agreed that there has been an increase in the number of women seeking contraception’s due to the perceived association of zika to microcephaly. 7% said there hasn’t been any major difference and 3% said that they do not know.

Zika Prevention Methods and Tools

Figure 2. The relative importance of tools and methods used by health centers to prevent and control zika in Cachoeira is shown. The size of each portion corresponds to the perceived effectiveness of the respective tool.

Education was ranked as the most effective tool in the prevention and control of zika, dengue and chikungunya. The work done by community health agents to visit houses and apply the Pyriproxyfen powder, a powder that prevents mosquito breeding in standing water areas, ranked second among the other methods. These data show that the community recognizes the work done by the community health workers and they have seen the positive effects of this work.

Perception of health care workers on the effectiveness of the tools and methods used by their health centers

The health care workers had differing opinions about the effectiveness of the tools and methods used by their health centers in the fight against zika, dengue and chikungunya. 93% of the health workers in Alecrim said they were not satisfied with the tools and methods employed by their health center in the fight against the infectious diseases. On the other hand, about 89% of the health workers at the Center for Endemic Diseases rated the effectiveness of the tools and methods employed by their health center a 5 and above. The Alecrim health center is in a rural part of Cachoeira, while the Center of Endemic Diseases is in the urban part. There are more cases of zika, dengue and chikungunya in the urban areas than in the rural areas, resulting in a greater concentration of efforts in the urban areas. For example, health centers in rural areas like Alecrim do not receive Pyriproxyfen powder to prevent mosquito breeding and thus the community health workers only rely on flyers and other educational materials to spread awareness in the community and in schools.

The concentrated efforts to control zika and other related infectious diseases in the urban areas may have proven to be fruitful as the number of zika cases has decreased significantly since the month of August 2015 to date. However, there is no absolute proof that the decrease has been due to the preventative methods in place. Other factors such as climate and weather conditions may play a major role in the habitats and breeding patterns of the mosquitoes, which transmit the diseases. Research shows that the Aedes aegypti mosquito adapts easily to human environments and like other species, the mosquito is evolving and forming new strains. These new strains are more resistant and may reach rural areas, which are now considered safer than urban areas (Schinrring 2016). Efforts to fight infectious diseases like zika and dengue will need diagonal approaches whereby both the rural and urban areas are well equipped and protected from further outbreaks. As of now, the rural areas are at high risk of an outbreak and this will probably be much harder to control because there are few health resources in the rural areas.

Challenges faced by the health centers in prevention of zika

More than 50% of the health worker respondents listed delay of test results as one of the major challenges facing the health centers in the fight against zika. Once a person arrives at the health center with symptoms, he or she must first be tested for both dengue and chikungunya. Once they rule out both diseases, then the person is confirmed to have zika. The problem is that the molecular testing of dengue, which detects the genetic material of the dengue virus in the blood, takes up to 5 days after symptom onset (fever). Antibody tests, which detect two different types of antibodies produced by the body in response to a dengue fever infection, may take 2 to 4 weeks. The tests for chikungunya are normally available 4 to 14 days after the specimen is collected. Unfortunately, in hot weather climates like Brazil, the reporting times for the test results may take longer because the arbovirus activity increases and thus takes longer to detect. Thus, it may take weeks for a person to be confirmed to have zika, which also affects reporting and planning of control measures.

Perception of health care workers on efforts made by the Brazilian government to control and prevent zika

Data from this research show that about 79% of the respondents rated the government’s efforts to control and prevent zika a 5 and below (10=the government makes great efforts to prevent zika, 1= the government is not making any efforts to prevent zika). However, none of the respondents rated it below a 3, which means they all perceive the government to be making some form of efforts.


The outbreak of zika in Brazil as well as the increase in the number of microcephaly in newborns has been an ongoing discussion among health experts, political leaders and economists. The same mosquito that carries dengue causes zika, and thus the outbreak of zika could suggest that the policies that were in place to fight dengue were not effective and successful. In this case, zika has been a necessary public health wake up call. Brazil’s political system has been unstable with ongoing strikes and protests. Efforts to fight zika will largely depend on leadership, and with the current political instability, a lot is at stake. The economy of the country has also been largely affected after the zika outbreak and with the increased numbers of babies with microcephaly, a lot of money will have to be invested in providing them with the necessary health needs as well as special education.

Due to the increase of congenital anomalies after the outbreak of zika in Brazil and neighboring countries, all member states should establish and maintain heightened capacity to detect and confirm zika cases and introduce public health measures to reduce risk of zika spread and infection.

It is important to ensure that health care providers are knowledgeable and up to date with the latest findings on zika because they play the primary role of care provision to the communities. Similarly, up-to-date information should be well shared among public health, political and religious leaders to ensure appropriate measure and actions are taken.

Limitations of the study

Language: Language barrier was one of the main limitations of this study. My level of Portuguese is still at beginners’ level and thus it was hard to fully understand people when in the field, and it was also difficult to fully participate in related conversations. Due to this, I think there is some important and useful information that I missed during these interactions. This challenge can be overcome by having the ability to speak and understand Portuguese at an intermediate or advanced level. Another way is by having a translator who is fluent in both Portuguese and English.

Time: Four weeks is a short time to fully engage in a new community and community study project. It takes time to get accustomed to a place’s new culture and way of living as well as establish contacts. Thus, although I was able to reach the goals of the project, I was able to do so in a small scale.


  1. Anglican News Service. (2016, February 12). Retrieved April 12, 2016, from http://www.anglicannews.org/news/2016/02/brazils-churches-respond-to-zika-virus-through-lent-campaign.aspx
  2. Ayres, C. F. (2016). Identification of Zika virus vectors and implications for control. The Lancet Infectious Diseases, 16(3), 278-279. doi:10.1016/s1473-3099(16)00073-6
  3. Bell, B. P., Boyle, C. A., & Petersen, L. R. (2016). Preventing Zika Virus Infections in Pregnant Women: An Urgent Public Health Priority. Am J Public Health American Journal of Public Health, 106(4), 589-590. doi:10.2105/ajph.2016.303124
  4. Facts about Microcephaly. (2016). Retrieved April 18, 2016, from http://www.cdc.gov/ncbddd/birthdefects/microcephaly.html
  5. Heukelbach, J. (2016). Zika virus outbreak in Brazil. Journal of Infection in Developing Countries, 10(2), 116-120. Retrieved April, 2016.
  6. Horan, E. (2016, January 29). Q&A: Mosquito-borne Zika virus linked with microcephaly in Brazil. Retrieved May 23, 2016, from http://thriving.childrenshospital.org/qa-zika-virus-mothers-linked-microcephaly-babies-brazil/
  7. Questions and answers. Zika virus and complications:(n.d.). Retrieved April 18, 2016, from http://www.who.int/features/qa/zika/en/
  8. Questions-Answers. (2016). Retrieved April 18, 2016, from http://www.cdc.gov/zika/pregnancy/question-answers.html
  9. Rodrigues, L. C. (2016). Zika: The Tragedy and the Opportunities. Am J Public Health American Journal of Public Health, 106(4), 582-582. doi:10.2105/ajph.2016.303114
  10. Schinrring, L. (2016, May 20). Cape Verde Zika virus matches Americas’ strain, threatening Africa. Retrieved May 23, 2016, from http://www.cidrap.umn.edu/
  11. Zika Virus Associated with Microcephaly — NEJM. (n.d.). Retrieved April 18, 2016, from http://www.nejm.org/doi/full/10.1056/NEJMoa1600651#t=article
  12. Zika virus microcephaly and guillain-barré syndrome (pp. 1-12, Rep.). (2016). World Health Organization


I thank God in heaven for all the guidance during this project. I also want to extend my warm gratitude to Gabriela Ventura, Dr. Rita Maluf, my host family in Alecrim and my family.

Categories: Uncategorized

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s