Seroprevalence and Genotype Diversity of Hepatitis C Virus in the Caribbean-A Review.

Hepatitis C (HCV) continues to present a global public health challenge, with no vaccine available for prevention. Despite the availability of direct-acting antivirals (DAAs) to cure HCV, it remains prevalent in many regions including the Caribbean. As efforts are made to eliminate HCV from the region, existing barriers, such as the high cost of DAAs and lack of an established database of HCV cases within the Caribbean, must be addressed. This review seeks to assess epidemiologic trends (seroprevalence and genotypic diversity) of HCV in the Caribbean and identify gaps in surveillance of the disease. The literature for the period 1 January 2005 to October 2022 was reviewed to gather country-specific data on HCV across the Caribbean. References were identified through indexed journals accessed through established databases using the following keywords: Caribbean, genotype distribution, and general epidemiologic characteristics. The usage pattern of HCV drugs was determined from information obtained from pharmacists across the Caribbean including Jamaica. The prevalence of HCV in the Caribbean was 1.5%; the region should therefore be considered an area of moderate HCV prevalence. The prevalence of HCV among intravenous drug users (21.9-58.8%), persons living with HIV/AIDS (0.8 to 58.5%), prisoners (32.8-64%), and men who have sex with men (MSM) (0.8-6.9%) was generally higher than in the general population (0.8-2.3%). Genotype 1 (83%) was most prevalent followed by genotypes 2 (7.2%) and 3 (2.1%), respectively. Less than 50% of countries in the Caribbean have reliable or well-curated surveillance data on HCV. Drugs currently being used for treatment of HCV infections across the Caribbean include Epclusa (sofosbuvir/velpatasvir) and Harvoni (ledipasvir/sofosbuvir). Some of these drugs are only available in the private sector and are sourced externally whenever needed. While trends point to a potentially higher prevalence of HCV, it will require well-designed random surveys to obtain better estimates of the infection seroprevalence, supported by strong public health laboratory systems. DAAs that are pan-genotypic should translate into treatments that are affordable, accessible, and available to improve cure rates and reduce the HCV burden in the population.

The performance of the SD BIOLINE Dengue DUO® rapid immunochromatographic test kit for the detection of NS1 antigen, IgM and IgG antibodies during a dengue type 1 epidemic in Jamaica.

BACKGROUND: Dengue is an important mosquito-borne viral infection that affects millions of persons worldwide. Early diagnosis is necessary to effect appropriate management and decrease mortality. Immunochromatographic tests are advantageous in producing dengue test results within 30 min but these results should be sensitive and specific. In this study we evaluated the diagnostic performance of the SD BIOLINE Dengue DUO® rapid immunochromatographic test kit. A panel of 309 dengue and 30 non-dengue single serum samples characterized by using reference enzyme-linked immunosorbent assays (ELISAs) was used. These samples were received in the virology laboratory for routine testing during a dengue type 1 outbreak between October to December, 2012. RESULTS: The overall diagnostic sensitivities of the SD BIOLINE Dengue DUO® rapid testfor IgM, IgG and NSI were 49.3% (95% CI: 41.3-57.4), 39.1% (95% CI: 33.3-45.2) and 90% (95% CI: 82.1-94.7), respectively. The IgM and IgG detection rates were significantly lower than that of the NSI (p < 0.001). However the combination of the IgM detection with NS1 detection or both NS1 and IgG resulted in a significant (p < 0.001) increase in sensitivity to 97.5% (95 % CI: 92.9-99.2) and 98.9% (95 % CI: 96.0-99.7), respectively. These higher sensitivities were achieved without any decrease in specificities. CONCLUSIONS: This study revealed that combining two or more parameters of the SD BIOLINE Dengue DUO® rapid kit significantly improved the sensitivity of diagnosis of dengue virus infection and supports its usefulness in the Jamaican setting.

Leptospirosis in suspected cases of dengue in Jamaica, 2002-2007.

Due to overlapping clinical features with other febrile illnesses, the diagnosis of leptospirosis is often overlooked, resulting in delay in treatment and increased mortality. In this study the prevalence of leptospirosis was determined in 590 patients with dengue-like illnesses using the Leptospira IgM dipstick and dengue enzyme-linked immunosorbent assays. Leptospira IgM antibodies were found in 27 (5.0%) patients. Dengue IgM negative (6.9% versus 2.5%, P < 0.05) and dengue IgG positive patients (8.0% versus 3.5%, P < 0.01) were more likely to be leptospira IgM positive. Fever, skin rash, central nervous system and respiratory involvement were the most common presenting features. The presence of arthralgia (P = 0.016), hepatitis (P = 0.000), jaundice (P = 0.003), splenomegaly (P = 0.041) and haematuria (P = 0.029) were associated with leptospirosis. In countries with an endemicity of leptospirosis and dengue it is important that patients with dengue-like illnesses, especially those with no serological evidence of current primary dengue infection, be investigated for leptospirosis.

Seroprevalence of dengue virus antibodies in healthy Jamaicans.

Dengue fever, a mosquito borne viral infection, is endemic to Jamaica. The seroprevalence of dengue IgG and IgM antibodies were determined in 277 healthy Jamaicans by enzyme linked immunosorbent assay (ELISA). The seroprevalence of dengue IgG antibodies was 100% (277/277) while dengue IgM antibodies were found in 3.6% (10/277). A statistically significant association was found between the presence of dengue IgM antibodies and gender (males 10/105, 9.5% vs females 0/172, 0.0%); chi(2) = 17.0, p=0.000.The high seroprevalence rate of dengue IgG antibodies and the presence of dengue IgM in the healthy population are in keeping with the endemicity of the virus in Jamaica. Therefore tests for dengue IgG antibodies are of limited usefulness in Jamaica and can be safely excluded from diagnostic testing as a cost saving measure. Serological diagnosis of current dengue infection should be centred around the dengue IgM tests although the limitations in the predictive values of such tests should also be considered. The results also suggest that the risk of emergence of the more severe forms of dengue, dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS) in the Jamaican population, due to the presence of enhancing antibodies, is high.

Patterns of dengue virus IgM and IgG antibodies in suspected cases of dengue in Jamaica, 2003-2006.

The patterns of dengue immunoglobulin (Ig) M and IgG antibodies in patients presenting with dengue-like illnesses during 2003-2006 were investigated using enzyme linked immunosorbent assays (ELISA). The seroprevalence of dengue antibodies, dengue IgM and dengue IgG antibodies were 59.4% (979/1647), 15.4% (254/1647) and 51.1% (841/1647), respectively. A statistically significantly increasing trend in the prevalence of dengue IgG antibodies with age was observed, ranging from 38.4% in patients aged less than 1 year to 90% in those 60 of years and over (p = 0.000; 95% confidence interval (CI) = 0.000-0.002). Conversely the seroprevalence of dengue IgM did not differ significantly with age and no seasonality in the number of cases was observed. The patterns of IgM and IgG antibodies found in the present study are consistent with those found in dengue endemic countries during inter-epidemic periods indicating that an increasing risk of a new dengue outbreak due to the accumulation of susceptible population. Preventive measures should be maintained to control the endemic spread and reduce the risk of outbreaks of dengue in Jamaica. The high seroprevalence rate of dengue IgG antibodies might have implications for the emergence of the more severe forms dengue infection in the Jamaican population.

Epidemiology of hepatitis A virus in Jamaica

OBJECTIVE: Between January 1995 and August 1998, a study was conducted to elucidate the epidemiology of hepatitis A virus (HAV) in Jamaica. DESIGN AND METHODS: Participants were recruited from seven sites located in rural and urban areas of Jamaica. There were 128 and 211 females. The ages of the participants ranged from 3 to 90 years. The average ages of males and females were 24.9 and 25.6 years, respectively. Social and demographic data were collected by questionnaire. Potential risk factors which were studied included age of the individual, gender residence in an urban and rural are, type of toilet facilities and source of domestic water supply (indoor or outdoor plumbing). RESULTS: The seroprevalence of HAV in the study population using ELISA was 59.9 percent. Based on logistic regression, age and source of domestic water supply were found to be the major contributors to exposure to HAV (p<0.001) and p=0.006, respectively). The rate of exposure to the virus increased with age. By age 10 years, 30 percent of children were exposed. This was followed by a steady increase to about 73 percent by age 30 years. Prevalence remained at a plateau up to age 50 years after which there was an increase to almost 100 percent in the oldest individuals. Rates of exposure to HAV were higher amongst households with outdoor plumbing which included standpipes, rivers and tanks than those with indoor plumbing. CONCLUSIONS: The seroprevalence of HAV in Jamaica is higher than that seen generally in developed countries, although the age related acquisition of infection was similar. It is expected that the pattern and severity of disease from the virus is similar to that seen in developed countries. Improved water supply and educating the public on the epidemiology of HAV could reduce the prevalence of HAV in Jamaica.(AU)

Rubella susceptibility in Jamaican women, 1996

The 1995 rubella outbreak in Jamaica indicated a need to survey the susceptibility rate in Jamaican antenatal women at risk. In this 1996 study, 389 women in the reproductive age group were investigated for rubella antibodies. In the public sector urban group (A), rubella susceptibility was 20.2 percent, while in a private sector urban clinic (B) practising routine rubella surveillance and recommending postpartum immunization in seronegatives, the susceptibility rate was 13.8 percent. The latter rate was 21.3 percent. Rubella susceptibility has improved overall in women of childbearing age compared with levels in the prevaccine year of 1968. A significant thrust in rubella prevention will still be required before the next rubella epidemic in order to reduce the risk of congenital rubella syndrome.(AU)

A study of the epidemiology of hepatitis A virus infection in the Jamaican population

Hepatitis A virus (HAV), is an RNA virus in the picornavirus family. It is transmitted faecal-orally by contaminated food drink. It has a worldwide distribution, and like other enteric infectious diseases it is typically an infection of childhood, related to conditions of crowding and poor hygiene. HAV causes only acute hepatitis and has never been associated with chronic liver disease such as seen with hepatitis B virus or hepatitis C virus. Infection with HAV may be prevented by improving levels of sanitation and hygiene and immunization with HAV vaccine. Between January 1995 and August 1998, 339 individuals were recruited into the study of the epidemiology of HAV. Sera from the participants were tested for anti-HAV IgG using the Enzyme Linked Immunosorbent Assay (ELISA) technique (Abbot Laboratories, Abbort Park, IL 60064). Social and demographic data were collected using questionnaires. The age of the participants ranged from 3-90 years. There was 128 males and 211 females. The average age of males and females was 25 years. The seroprevalence of HAV in the population using ELISA was 59.9 percent. Age and source of water supply were found to be the major contributors to exposure to HAV. The seroprevalence of HAV in Jamaica is higher than the seen generally in developed countries, although the age related acquisition was similar. Improved water supply, educating the public on the epidemiology of HAV and immunization in the preschool age children could reduce the prevalence of HAV in Jamaica.(Au)

Investigations of central nervous system viral infection at UHWI, 1998-1999

Preliminary results are presented for viral infections of the CNS at UHWI between July 1998 and June 1999. A total of 168 cases were referred from the following hospitals and distributed as follows: UHWI 119 (70 percent); Bustamante Children's 31 (18 percent); Spanish Town 10 (6 percent); Kingston Public 7 (4 percent); Other 2 (1 percent). Specimens received were acute and convalescent sera, throat swabs, rectal swabs and CSF. Laboratory investigations included viral culture and serology; confirmatory methods included neutralization tests, immunofluorescence (IFA) and polymerase chain reaction (PCR). The clinical diagnoses in the 168 cases included for viral CNS investigations were submitted from only 47/168 (30 percent) of cases. Viral agents were identified in 31/47 (66 percent) of the appropriate specimens received. These viruses included enteroviruses 12/31 (38 percent), human immunodeficiency virus (HIV) 9/31 (29 percent), 3/31 (9 percent) of the HIV positive patients were also positive for toxoplasmosis), dengue 6/31 (19 percent), herpes simplex virus 1/31 (3 percent), rotavirus 1/31 (3 percent), cytomegalovirus 1/31 (3 percent) and influenza 1/31 (3 percent). Enteroviruses, HIV and dengue were the viruses most frequently associated with CNS infections among the 31 cases identified. This however is not a complete representation of CNS associated with viral agents, as appropriate specimens were received from only 30 percent of the cases. This study also demonstrated a definite need for an increased understanding of appropriate specimen collection and submission necessary for the diagnosis of viral CNS infections.(AU)