Isolation and Complete Genome Sequencing of Zika Virus Imported from the Dominican Republic to Japan

Breeding Sites of Synanthropic Mosquitoes in Zika-Affected Areas of the Dominican Republic

Mosquito-borne diseases are a major public health concern in the Caribbean. Domestic water-storage containers are preferred breeding habitats for synanthropic mosquito species, among which Aedes aegypti stands out due to its role in arbovirus transmission. To determine the microenvironmental features associated with container-dwelling mosquitoes, a house-to-house cross-sectional entomological survey was carried out in 9 Dominican provinces affected by Zika virus in 2016. All containers with the potential to store water were sampled, all immature mosquitoes were collected, and information on the type, capacity, volume of stored water, building material, presence of flowers, and house location was documented. The specimens were identified and larval indices (House index [HI], Container index [CI], Breteau index [BI], and Ae. aegypti Breeding Percentage) were applied. A total of 665 dwellings were surveyed across 30 neighborhoods. A total of 1,420 water-filled container habitats were sampled, 19.3% of which harbored immature mosquitoes of 5 species, including 4 important vectors. The dominance of Ae. aegypti was marked, as it was present in all sampled neighborhoods, inhabiting 272 containers (19.1%). Larval indices were higher than the threshold values accepted (5% for the HI and BI, and 3% for the CI) in almost all neighborhoods. The presence of Aedes spp. was associated with the serviceability of water-holding containers (χ2 = 16.56522; P < 0.001), and the difference in volume between water-holding containers was associated with the presence of Aedes spp. infection (χ2 = 4; P < 0.001), the containers up to 5 liters being the most infested. This is the first entomological research based on synanthropic mosquito breeding habitats that cover urban areas of the 3 macro-regions of the Dominican Republic.

[The Recent Epidemic Spread of Zika Virus Disease]

Zika virus (ZIKV) is one of the members of the Spondweni serocomplex within the genus Flavivirus of the family Flaviviridae. The virus was first isolated from a serum specimen from a sentinel non-human primate in the Zika forest of Uganda in 1947. ZIKV is transmitted by Aedes aegypti and A. albopictus in an urban cycle and maintained in a sylvatic cycle between Aedes mosquitoes and monkeys in Africa and Asia. Initially, the virus was thought to cause only mild and nonspecific clinical symptoms in humans. However, ZIKV became a serious public health concern in recent years due to an association with congenital malformation known as microcephaly in newborns as well as Guillain-Barré syndrome and other neurologic disorders in adults. The severe nature of complications of ZIKV infection have led to an urgent need for a safe and effective vaccine worldwide including Japan. The first large outbreak of disease caused by ZIKV infection was reported from the island of Yap, Micronesia in 2007. It was followed by outbreaks in French Polynesia, Cook Islands, Ester Island, and New Caledonia in 2013 and 2014. In 2015, ZIKV outbreak was reported in Brazil and has spread across the Latin America, and the Caribbean. The exact prevalence of ZIKV infection has not been reported because of the absence of a standardized protocol for differential diagnosis and its clinical resemblance to dengue virus and other flavivirus infections. In Japan, the first human case of ZIK fever, who developed illness soon after returning from French Polynesia, was reported in 2013, and until 2017, 20 imported cases were documented. Currently, research on ZIKV has progressed remarkably thus this article aims to review recent progress in virology, epidemiology, and pathology of ZIKV infection.

Knowledge and perceptions of Zika virus transmission in the community of Puerto Plata, Dominican Republic

Background

Zika virus is associated with increased cases of both microcephaly and Guillain-Barré syndrome. Community knowledge, perceptions and practices to prevent infection with the Zika virus are not well understood, particularly among high risk populations living in resource-poor and Zika-endemic areas. Our objective was to assess knowledge of symptoms, health effects and prevention practices associated with Zika virus in rural communities on the northern coast of the Dominican Republic.

Methods

Study participants were contacted while attending community events such as free medical clinics and invited to be interviewed regarding their knowledge, attitudes, and perceptions of Zika virus using the World Health Organization’s Zika survey tool.

Results

Of the 75 Dominicans that participated, 33% did not know who could become infected with Zika. In addition, only 40% of respondents were able to identify mosquitoes or sexual transmission as the primary routes of infection though 51% of respondents thought that Zika was an important issue in their community.

Conclusions

This study found that general knowledge regarding the basic risks and transmission of Zika were not well understood among a sample of rural Dominicans. Our findings highlight disparities in knowledge and perception of risk from Zika in rural areas compared to previous studies conducted in the Dominican Republic. Education about the basic risks and transmission of Zika are critically needed in these remote populations to reduce Zika transmission.