Epidemiology: Zika Virus Essay

Abstract

Zika virus (ZIKV) belongs in the Flavivirus genus, which consists of other 52 viral species capable of being transmitted by mosquitoes and ticks, among other arthropod vectors (Song et al., 2017). Moreover, within this genus, the ZIKV is regarded as a mosquito-borne virus that holds a phylogenetic relationship to other mosquito-borne flaviviruses of significant global public health concern.

Spread of Zika Virus across International Borders

Virus Spread in Africa and Asia before the Year 2000

It was initially discovered in 1947 in Uganda when it was isolated from the sera of the sentinel rhesus macaque monkey that was placed in the Zika forest to surveil YFV (Song et al., 2017). Momentarily after, it was identified in the Aedes Africanus mosquitoes habituating in the same region. Later serological studies evidenced widespread but confined prevalence of the ZIKV across the narrow equatorial belt running from Africa to Asia (Song et al., 2017). These included countries, such as Sierra Leone, Uganda, Senegal, Gabon, Nigeria, Kenya, Egypt, Central African Republic, India, Tanzania, Thailand, Pakistan, Malaysia, Indonesia, the Philippines, and Indonesia. The first non-African ZIKV strain was detected in 1967 in Malaysia from the A. aegypti.

Spread of the ZIKV to the Yap Island and South East Asia between the Late 2000s to Mid-2010s

In 2007, the first largest outbreak of ZIKV outside Asia and Africa was on Yap Island, part of the Federated States of Micronesia (Song et al., 2017). This is on the northwest of the Pacific Ocean. Studies reveal that the virus entered Yap Island via Southeast Asia. In the early to mid-2010s, relatively few cases were reported in Southeast Asian countries consisting of Indonesia, Thailand, Cambodia, Malaysia, and the Philippines.

The outbreak in French Polynesia and the Pacific Islands in the early 2010s

In the years 2013 and 2014, a significant outbreak of ZIKV ensued in a French overseas territory found in the middle of the southern Pacific Ocean, French Polynesia (Song et al., 2017). Even though the source of the virus in this region remains unknown, research has revealed that it is genetically related to Cambodia’s strains in 2010 and Yap Island’s in 2007 (Song et al., 2017). Later on, ZIKV expanded to other neighboring islands in the South Pacific Ocean between 2014 and 2016 (Song et al., 2017). It affected the Cook Islands, New Caledonia, and Easter Island. Furthermore, it spread to other distant countries, such as Japan, Australia, Italy, and Norway.

Outbreak in Brazil and Spread in America between 2015 and 2016

The first case of ZIKV in Brazil was discovered at the beginning of 2015 in the northern region of Brazil (Song et al., 2017). After its emergence in Brazil, the virus has been spreading at a relatively fast rate throughout South and Central America, and the Caribbean.

Epidemiological Determinants and Risk Factors

Research suggests that most individuals without prior exposure to ZIKV are more susceptible to infection (Obore et al., 2019). Inhabitants of regions with the ongoing vector-borne transmission of the virus are susceptible to disease. Moreover, mosquitoes tend to breed in contaminated aquatic environments, such as stagnant water; therefore, people with homes around such areas are prone to vector-borne ZIKV infection. Mosquito larvae and pupae can take up the virus from the contaminated aquatic environments, thereby leading to ZIKV infected adult insects. Nevertheless, unlike other species, the A. Aedes mosquito is predominant in urban areas where it breeds in indoor and outdoor settings, such as flower vases, rubber tires, and water storage tanks. Thus, homes with unscreened or open windows, particularly in areas with ongoing ZIKV transmission, are highly susceptible to infection.

Studies also link sexual transmission, specifically from travelers or individuals from endemic regions returning to other areas without vector-borne transmission (Obore et al., 2019). Other social factors that affect ZIKV infection comprise high population density and poverty that heighten the probability of transmission and infection. Impoverished people often have low-quality housing, unscreened windows, and poor drainage that leads to greater mosquito abundance and biting rates. Aside from human factors, environmental factors like temperature and humidity favor mosquito breeding; therefore, they play a significant role in sustaining the vector population.

Route of Transmission of the Zika Virus

The virus is primarily transmitted through the bite of infected mosquitoes; however, it can also be passed via other non-vector-borne methods. These different types of transmission make it challenging to formulate control and prevention strategies against the virus.

Vector-borne Transmission

ZIKV transmitted by the mosquito has two distinct transmission cycles, including the sylvatic and urban cycles. The sylvatic process entails the maintenance of the virus between mosquitoes in the forests and non-human primates. On the other hand, the urban cycle comprises the maintenance of the virus between mosquitoes and humans in urban areas. ZIKV has been identified in the serum of several mosquito species in the Aedes genus. This comprises the A. africanus, A. aegypti, A. furcifer, A. look, A. albopictus, A. vittatus, A. apicoargenteus, A.luteocephalus. However, the A. albopictus, the Asian tiger mosquito, and A. aegypti, the yellow fever mosquito, are considered to be associated with the highest transmission rates (Song et al., 2017).

Non-vector borne transmission

Direct human-to-human transmission of the virus has been identified to be primarily transmitted through sexual relations, blood transfusion, and breastfeeding. The virus can be transmitted from an infected mother to her child during pregnancy. This is illustrated by the presence of the ZIKV RNA in the urine, amniotic fluid, and serum of mothers whose babies were found to have brain abnormalities (Song et al., 2017). The RNA has also been detected in breastmilk, hence, indicating that they have a probable risk of being transmitted through breastfeeding. On the other hand, sexual transmission is evidenced by the presence of the virus in the semen of an infected individual. However, male-to-female transmission tends to occur more than female-to-male or male-to-male transmission (Song et al., 2017). Lastly, although uncommon, a direct transmission might also occur via the skin or mucous membranes (Song et al., 2017).

Effect of the Zika Virus on the Florida Community

Overall, the ZIKV hurts the community at a systems level. Local governments are usually at the frontline of the outbreak, and this would be due to the heightened spending on Medicaid and public health. The local government will have to reallocate general revenue funds or identify supplemental appropriations to enable the local public health agencies to manage the virus. This would offset their current budgets, and to balance it, this would mean making cutbacks with reduced spending, higher tax rates, or fees. Higher tax rates would adversely affect consumer spending; thus, having a rippling effect on businesses due to the increased price of goods.

Furthermore, ZIKV would put a strain on hospitals, especially on pregnant mothers who are highly at risk of transmitting the virus to their fetuses or babies through breastmilk. ZIKV has been associated with other neuropathies, such as Guillain– Barré syndrome (GBS), microcephaly, and brain abnormalities (Song et al., 2017). According to the Centers for Disease Control and Prevention (2019), approximately one in seven babies exposed to the virus before birth had one or more health concerns caused by Zika. Some were apparent at birth; however, others became apparent as the babies grew older. This would strain the health systems as more personnel with relevant expertise are required to deal with the outbreak. Moreover, more social workers, speech, physical, and occupational therapists would be required to care for babies born with Zika-associated defects. Lastly, Zika-associated congenital disabilities would pressure the education system as teachers would require training on how to facilitate learning among children with brain abnormalities, visual and hearing impairments.

Reporting Protocol of a Zika Outbreak in the Florida Community

According to the Florida Health Government (2018), all health practitioners are obligated to notify the Florida Department of Health as ZIKV falls under the list of diseases and conditions of public health significance under Chapter 64D-3.029 of the Florida Administrative Code. Moreover, the law states that a laboratory report of test results is insufficient to disregard the practitioner’s duty to alert the Department of the viral infection. This is because the Department is reliant on such notifications to assess the community’s health and direct preventive action. Furthermore, ZIKV falls under the list of diseases meriting notice upon suspicion (referred to as Suspect Immediately) that should be reported at any time of the day, week, or month (Florida Health Government, 2016). Such diseases are of immediate public health concern because of their highly infectious nature. Practitioners are required to make a phone call following initial clinical suspicion. The aim of the ‘Suspect Immediately’ timeframe it alert the public health authorities to provide the required response, for instance, prophylaxis or issuing a mosquito control notification to prevent further exposure.

ZIKV Outbreak Prevention Strategies

Since there is no known cure for ZIKV and measures of preventing prenatal mother-to-fetus transmission, personal protection, and home vector control measures are the only feasible ones. Implementation of ZIKV prevention behavior promotion intervention is essential in maximizing these self-protective behaviors. Such interventions can change behavior by tackling behavioral barriers, creating incentives, and enhancing individuals’ capabilities to embrace the behavior. Health education can be facilitated by either or both patient and community education strategies. As patient advocates, health practitioners have a significant impact on helping them change their health behaviors. For instance, nurses are often in a position to detect early symptoms of an infection; therefore, playing an essential role in recognizing and reporting outbreak situations. As a result, it is their responsibility to assist in the control of the spread of ZIKV. To effectively support patients diagnosed with ZIKV and the community at large, nurses are required to keep current with the latest information and guidelines. This might entail conducting door-to-door visits to educate the community regarding preventing transmission and protecting themselves from the virus.

Other educative opportunities comprise print, television, radio, and social media channels to strategically disseminate prevention information. On the other hand, in a patient setting, particularly among patients diagnosed with ZIKV, nurses can advise them on pathways of viral transmission and enlighten their patients on how to protect others. For women of reproductive age and their sexual partners, practitioners can offer counseling and propose delayed pregnancy as suggested by the World Health Organization (World Health Organization, 2016). Furthermore, including their partners in such discussions might prove crucial as both parties will recognize the significance of delaying pregnancy and participating in safe sex to facilitate disease prevention.

References

Centers for Disease Control and Prevention. (2019). Zika virus. Web.

Florida Health Government. (2016). Health care practitioner reporting guidelines for reportable diseases and conditions in Florida. Web.

Obore, N., Papabathini, S., Ghimire, U., Kawuki, J., & Musa, T. (2019). Zika virus in Africa: Epidemiology and determinants. Journal of Advances in Medicine and Medical Research, 30(11), pp. 1-13. Web.

Song, B., Yun, S., Woolley, M., & Lee, Y. (2017). Zika virus: History, epidemiology, transmission, and clinical presentation.Journal of Neuroimmunology, 308, pp. 50-64. Web.

World Health Organization. (2016). Zika virus. Web.