Use of Envelope Domain III Protein for the Detection of IgG Type Antibodies Specific to Zika Virus by Indirect ELISA.

Zika virus (ZIKV) diagnostics are crucial for proper antenatal and postnatal care and also for surveillance and serosurvey studies. Since the viremia during ZIKV infection is fleeting, serological testing is highly valuable to inform diagnosis. However, current serology tests using whole virus antigens frequently suffer from cross reactivity issues, delays, and technical complexity, especially in low and middle income countries (LMICs) and endemic countries. Here, we describe an indirect ELISA to detect specific IgG antibodies using the ZIKV envelope domain III (EDIII) protein expressed in Drosophila S2 cells as an immunogen. Using a total of 367 clinical samples, we showed that the EDIII-ELISA was able to detect IgG antibodies against ZIKV with high sensitivity of 100.0% and specificity of 94.7% when compared to plaque reduction neutralization tests (PRNTs) as the gold standard and using 0.208 as the cut-off OD value. These results show the usefulness of the recombinant envelope domain III as an alternative to standard whole virus proteins for ZIKV diagnostics as it improves the sensitivity and specificity of IgG ELISA assay when used as an immunogen. This method should, therefore, be extended to serological diagnostic techniques for other members of the flavivirus genus and for use in IgM diagnostic testing.

COVID-19 in Cabo Verde: an assessment of the first six months of the pandemic in the country.

Background: COVID-19, or the new coronavirus, has spread globally since its emergence in December 2019, bringing enormous global health and socioeconomic challenges. Egypt confirmed the first case of COVID-19 in Africa on February 14, 2020, while Cabo Verde confirmed the first case on March 19, 2020. Contrary to forecasts that the virus would swiftly spread throughout Africa, which would soon become the infection's epicenter, the evolution of the pandemic on the continent over the investigated time period has been slower than expected. Objective: This study aims to comprehend the progression and consequences of the COVID-19 pandemic in Cabo Verde during its first six months of existence. After the first confirmed case of the new coronavirus, on March 19, 2020, the government of Cabo Verde closed its international borders. Consequently, a state of emergency was declared with stringent restrictions on the movement of persons and goods. Additionally, facilities for the isolation of sick individuals, including field hospitals, had been established. To aid the most vulnerable, public and private organisations had organized fundraising drives. Results: Despite the use of mitigation techniques, the pandemic in Cabo Verde has caused severe socioeconomic harm. It is crucial to preserve and strengthen active surveillance, infection control, and risk communication methods. Social protection policies and economic incentives have the potential to boost infection control strategies.

Knowledge, attitudes and practices towards COVID-19: A cross-sectional study in the resident cape-verdean population.

CONTEXT: The first case of COVID-19 in Cabo Verde was confirmed on March 19, 2020. Since the beginning of the pandemic in the country, the government and health authorities have adopted restrictive measures to prevent the spread of SARS-CoV- 2 and well as defined risk communication and community involvement strategies. The present study aimed at assessing the knowledge, attitudes, and practices of the Cape Verdean resident population towards COVID-19, to support the government and the national health system in the definition of public health policies related to COVID-19. METHOD: A cross-sectional study was conducted among 1996 participants aged 16 years old and above. Data collected from April 5 to April 12, 2020, via an online self-reporting questionnaire adapted from a Chinese study. Descriptive statistics, chi-square tests, simple and multiple linear regression analyses were performed to determine factors associated with knowledge, attitudes, and practices towards COVID-19. RESULTS: The overall correct answer rate related to the knowledge about COVID-19 was 82% (9/11 * 100), 1970 (98.70%) of the participants declared they had stayed at home in recent days, 1926 (96.49%) had not attended parties, funerals or crowded places and 1860 (93.19%) confirmed changes in daily routines due to COVID-19. The majority of the participants, 1797 (90.26%), preferred receiving information about COVID-19 in Portuguese and trusted information transmitted by health professionals. Furthermore, television, radio, and newspapers were the preferred means of transmitting information about COVID-19. Participants' knowledge influenced COVID-19 prevention and control practices (rho = 0.119; p = 0.000). CONCLUSIONS: These findings showed that the resident population had a good level of knowledge about COVID-19; however, there is a need to use more effective strategies to improve attitudes and practices towards COVID-19 to attain better results in controlling the pandemic in Cabo Verde.

Genomic Epidemiology of 2015-2016 Zika Virus Outbreak in Cape Verde.

During 2015-2016, Cape Verde, an island nation off the coast of West Africa, experienced a Zika virus (ZIKV) outbreak involving 7,580 suspected Zika cases and 18 microcephaly cases. Analysis of the complete genomes of 3 ZIKV isolates from the outbreak indicated the strain was of the Asian (not African) lineage. The Cape Verde ZIKV sequences formed a distinct monophylogenetic group and possessed 1-2 (T659A, I756V) unique amino acid changes in the envelope protein. Phylogeographic and serologic evidence support earlier introduction of this lineage into Cape Verde, possibly from northeast Brazil, between June 2014 and August 2015, suggesting cryptic circulation of the virus before the initial wave of cases were detected in October 2015. These findings underscore the utility of genomic-scale epidemiology for outbreak investigations.

Abundance and Updated Distribution of Aedes aegypti (Diptera: Culicidae) in Cabo Verde Archipelago: A Neglected Threat to Public Health.

BACKGROUND: Mosquito-borne viruses, such as Zika, dengue, yellow fever, and chikungunya, are important causes of human diseases nearly worldwide. The greatest health risk for arboviral disease outbreaks is the presence of the most competent and highly invasive domestic mosquito, Aedes aegypti. In Cabo Verde, two recent arbovirus outbreaks were reported, a dengue outbreak in 2009, followed by a Zika outbreak in 2015. This study is the first entomological survey for Ae. aegypti that includes all islands of Cabo Verde archipelago, in which we aim to evaluate the actual risk of vector-borne arboviruses as a continuous update of the geographical distribution of this species. METHODS: In order to assess its current distribution and abundance, we undertook a mosquito larval survey in the nine inhabited islands of Cabo Verde from November 2018 to May 2019. Entomological larval survey indices were calculated, and the abundance analyzed. We collected and identified 4045 Ae. aegypti mosquitoes from 264 positive breeding sites in 22 municipalities and confirmed the presence of Ae. aegypti in every inhabited island. Results: Water drums were found to be the most prevalent containers (n = 3843; 62.9%), but puddles (n = 27; 0.4%) were the most productive habitats found. The overall average of the House, Container, and Breteau larval indices were 8.4%, 4.4%, and 10.9, respectively. However, 15 out of the 22 municipalities showed that the Breteau Index was above the epidemic risk threshold. CONCLUSION: These results suggest that if no vector control measures are considered to be in place, the risk of new arboviral outbreaks in Cabo Verde is high. The vector control strategy adopted must include measures of public health directed to domestic water storage and management.