Chikungunya in the western hemisphere: a review of the 2014 epidemic, the potential long-term impact, and research opportunities

OBJECTIVE: The objective of this paper is to present a comprehensive review of the impact of the recent chikungunya virus outbreaks in island nations, including the Caribbean, and explore the potential for further study of the epidemiology and pathogen-host interactions of this emerging virus. DESIGN AND METHODS: We conducted a review of the current literature and data on multiple facets of chikungunya including: acute disease outbreaks, epidemiological and clinical data, comparisons of diagnostic techniques, and virologic strains. RESULTS: Outbreaks of chikungunya (CHIKV) on island nations have seen high attack rates with corresponding increased morbidity and mortality. Severe, persistent and relapsing arthritis and tenosynovitis is common among chikungunya patients. CONCLUSION: Comprehensive surveillance of chikungunya virus is required by the linking of epidemiologic, molecular and immunologic data with information on ecological patterns and vector prevalence if the incidence of chikungunya is to be reduced and prevented. More data on the disease spectrum and persistence in the Caribbean nations, the viral strain, and the incidence rates are sorely needed. Because CHIK can only be prevented by preventing mosquito bites, more research needs to be done locally in Caribbean nations to determine the optimal strategies of Aedes vector control and public health education with subsequent behavior change.

Clinical, molecular and serological outcomes of the Chikungunya outbreak in Grenada

OBJECTIVE: This study evaluated the clinical utility of Chikungunya (CHIKV) test results and clinical symptoms in patients with suspected CHIKV infection. DESIGN AND METHODS: Patients with CHIKV symptoms who presented at a health facility in Grenada during the recent outbreak had a CHIKV diagnostic test form completed by a health professional and a blood sample was drawn. The serum sample was stored at -80oC, shipped to the Naval Infectious Diseases Diagnostic Lab (NIDDL) on dry ice and tested for CHIKV and Dengue (DENV) using PCR real-time assay for viral RNA, and IgM detection by ELISA. RESULTS: Sera from more than 600 patients collected from mid September till mid October, 2014 were drawn and had a CHIKV diagnostic form completed. At the time of writing 112 patients sera have been tested at the NIDDL. 90% of patients had a positive test. PCR only was positive in 8% of patients. IgM only was positive in 83%, and both PCR and IgM were positive in 9% of patients. The major symptoms presented by patients were joint pain (84%), fever (81%), body pain (74%), headache (62%), chills (54%) and rash (49%). CONCLUSION: IgM testing detected 92% of test positive patients while PCR alone detected 17%. The IgM assay was clinically most useful. In an outbreak where dengue is ruled out and CHIKV is the cause, patients with the constellation of symptoms above could be considered positive for CHIKV infection with a 98% accuracy without confirmatory testing.

The current prevalence and potential elimination of the soil transmitted helminth’s from Grenada

OBJECTIVE: This study formed part of a soil transmitted helminth elimination program in Grenada. The study assessed the prevalence of soil transmitted helminths (STH’s) in Grenadian primary school children. DESIGN AND METHODS: A longitudinal study was carried out on students attending 39 out of all 54 (72.2%) primary schools in Grenada, Carriacou and Petite Martinique between March 2013 and December 2014. The schools were randomly selected for inclusion in the study. Zinc Sulphate Floatation with centrifugation and Microscopy was used to assess the prevalence of STH’s in stool samples from Grenadian primary school children. RESULTS: The overall prevalence of STH was 1.3% (95% CI= 0.54-2.72). In 4 of the 8 parishes the prevalence was 0%. The highest prevalence was 3.9% (0.48-13.46) in St. Patrick. The STH identified were Ancylostoma duodenale, Ascaris lumbricoides and Trichuris trichuria. CONCLUSION: The prevalence of STH’s in the initial survey was 1.3%. This low prevalence indicates that the elimination program which utilizes a multi pronged approach including targeted chemotherapy and education may be feasible.

A ten year retrospective analysis of motor vehicle accidents in Grenada

OBJECTIVE: To assess the burden of Motor Vehicular Accidents in Grenada during the period 2000-2009. DESIGN AND METHODS: A cross-sectional study of secondary data in the form of vehicular accident records were sourced from the Royal Grenada Police for the period 2000-2009. Detailed records of the number of motor vehicle accidents per month and per year were sourced including the type of vehicle, the number of passengers, time and location of the accident and the gender and age of the drivers were not considered to be important. The adverse health outcomes of the accidents were also determined as either minor or major depending on fatalities and extent of injuries sustained. RESULTS: There has been an increase in the total number of fatalities during the period of study occurring from motor vehicle accidents from 4.1 in 2000 to 11.9 in 2009 per 100,000. The average increase in the number of total road accidents also rose by 8.9% in the stated period. In addition, the number of major and minor road accidents had steadily increased together with an increase in the number of vehicles registered. The burden of injuries varied across different periods of time over the course of review. Conclusion: From 2000-2009, there was steady increase in the total number of motor vehicle accidents, and fatal road accidents in Grenada.

An evaluation of the burden of diabetes in Grenada

OBJECTIVE: To assess the burden of diabetes in Grenada in terms of changes in quality of life and trends of incidence, amputation and gender. DESIGN AND METHODS: A mixed methods approach was used in which statistical retrospective analysis determined trends of diabetic related amputations based on secondary data for the period 2008-2012. A qualitative approach was also used to assess perceptions of quality of life of diabetic related amputees using interviews. RESULTS: There were no statistically significant differences or trends (relationships) found between number of amputations and incidences of diabetes with respect to time. The quality of life of diabetics decreased after receiving an amputation surgery as a result of multifactorial issues such as feelings of loneliness and financial instability. CONCLUSION: The decreasing trend of diabetes in Grenada was found to be statistically insignificant while quality of life of amputees was shown to be lowered. Decreasing the incidence of amputations should involve focus on the role of peripheral neuropathy. Policy development to increase benefits to disabled citizens is recommended to improve quality of life of Grenadians.

Impact of dropping out of the Sports for Health Program in Grenada

OBJECTIVE: To determine if there were any significant differences in body mass index (BMI) and waist-to-hip ratio (WHR) between active participants in the Sports for Health program and participants who were lost to drop out. DESIGN AND METHODS: Persons who were originally part of the program and data collection in 2011, but were no longer active participants were evaluated. The evaluation utilized the data from the participants at their last BMI and WHR measurements as program participants and follow up measurements as non-participants in 2014. RESULTS: Data analysis showed that body mass index (BMI) was signficantly higher in persons who no longer participated in the sports for health program when compared to active program participants. In addition, non-participation of persons in the Sports for Health program was found to increase individual risk factors for chronic diseases, which were originally mitigated by participation in the program. Barriers to participation by many women in the program included lack of partner support and negative community perceptions, which influenced several women to discontinue their participation in the program. Recommendations were made in order to address the barriers to participation and to decrease the drop out rate in the Sports for Health program in Grenada. CONCLUSION: Non-participation in the Sports for Health program adversely affects persons BMI and WHR, therefore, increasing risk factors for several non-communicable chronic diseases.

Lessons learnt from the intense 2014 Chikungunya Epidemic in Grenada

OBJECTIVE: To present an overview of the lessons learnt from the fall 2014 outbreak of Chikungunya (CHIK) in Grenada. DESIGN AND METHODS: A review of newspaper articles, news reports and opinions of clinicians and policy makers on the impact and evolution of the CHIK outbreak in Grenada was conducted. RESULTS: CHIK outbreaks on small island developing nations are characterized by high attack rates. The speed of the spread of the virus is facilitated by the efficient domesticated diurnal vector species Aedes aegypti. Efforts to educate the public and to control this vector stretched resources. Clinical attack rates in the Grenada outbreak impacted manpower resources in every sector including clinical services. CONCLUSION: CHILK infected an estimated 60% of the population in just three months of intense transmission. The resulting morbidity meant that essential lessons were learnt. These included the need for a rapid response in educating the population on the mode of transmission of the virus and its prevention, the implementation of vector control and the demand for diagnostic tests. Essential services were short staffed. The need for an unprecedented rapid response and the impact of the CHIK outbreak in Grenada will be presented.

Establishment of laboratory testing capability for chikungunya virus in Grenada, West Indies

OBJECTIVE: Rapid diagnosis of Chikungunya (CHIKV) is important early in an epidemic. The study objective was to describe the process of implementing CHIKV testing capability in Grenada and to confirm the arrival of CHIKV on the main island of Grenada. DESIGN AND METHODS: In April, 2014 a collaborative study between the U.S. Naval Infectious Diseases Diagnostic Laboratory (NIDDL) and the clinical microbiology laboratory of St. George’s University (SGU) was started. SGU acquired essential instrumentation and patient samples, and NIDDL provided supplies and reagents, plus technical training experts. RESULTS: Personnel, supplies and equipment arrived in Grenada in August 2014. Set up of instruments and test validation were completed quickly. Initial CHIKV PCR and IgM tests found 3 PCR positive samples. The IgM assay found several presumptive positives that were unable to be confirmed due to ELISA instrument malfunction. PCR data indicated that CHIKV had arrived on the main island of Grenada no later than August, 2014. Based on arbovirus test demand, symptomatic patients began to increase in August, peaked in September, and tailed off during November. CONCLUSION: Both CHIKV tests were implemented and produced the first on-island reference test confirmation of CHIKV patients in Grenada. The most difficult part of this effort was training technologists in time to help with testing. Laboratory testing for CHIKV infection can be a challenge in developing states at a distance from support services. Collaborative links with established labs remains essential.

A retrospective case series study of the seroprevalence of Human T Lymphocyte Virus 1 and 2 from the General hospital Laboratory in Grenada

OBJECTIVE: HTLV-1 is a human retrovirus that causes adult T-cell Leukemia/Lymphoma (ATL) and some other conditions – HTLV-associated myelopathy (tropical spastic paraparesis, a multiple sclerosis-like disease), uveitis, infective dermatitis and some “auto immune” diseases. While the Caribbean has been identified as an HTLV-1 endemic area, there are no published studies on HTLV-1 from Grenada. The objective of this study was to anonymously review the General Hospital laboratory records to investigate the seroprevalence of HTLV-1 and 2 in Grenada. DESIGN AND METHODS: This was a retrospective study of the records from the General Hospital Laboratory in Grenada, where ELISA serologically positive results for HTLV 1 and 2 were recorded as a percentage of the total number of tests performed between the years 1998 - 2013. The Diasoren rapid ELISA serological test was used. RESULTS: During the 16 year review period (1998-2013) a total of 2,346 (4.7%: 95% CI: 4.5% to 4.9%) out of 49,782 patients were identified as HTLV-1 and 2 positive. Females with a median age of 34 years comprised 70% of positive cases whilst the median age for males was 43 years. The rate in Grenada has been steadily declining since 1998 and appears to be leveling off at about 3.7%. CONCLUSION: The current seroprevalence of HTLV 1 and 2 in Grenada is lower than that reported in 1991 in Jamaica (5%). The rate found is still unacceptably high and additional studies are required to determine the health consequences of HTLV-1 infection. Additionally appropriate public health programs should be applied to help reduce transmission.

Short and long term knowledge of the transmission and prevention of soil transmitted helminths in primary schoolchildren assessed using Turning Point Technologies

OBJECTIVE: This study formed part of a soil transmitted helminth (STH) elimination program in Grenada. This study assessed the short and long term knowledge of primary school children on the transmission and prevention of STH using Turning Point Technologies. DESIGN AND METHODS: A longitudinal study was carried out on schoolchildren attending 39 out of all 54 (72.2%) primary schools from Grenada, Carriacou and Petite Martinique between March and November 2014. The schools were randomly selected for inclusion in the study. Turning Point Technology was used to assess the knowledge and administer the subsequent intervention to all students. The Pre, immediate-Post and long-term Post intervention (seven months later) data was analyzed using Chi Square. RESULTS: A total of 962 students participated in March 2014 and 805 students participated in October 2014. There was no significant (p< 0.05) inter school difference in the answering of questions. This displayed a ubiquitous knowledge transfer across the primary schools. There was a significant improvement in knowledge post turning point intervention, which was maintained at 7-months post-intervention. CONCLUSION: The advantages of using turning point technologies to impart this knowledge where class responses appear instantly, anonymously and can be used for immediate discussion were numerous. These include inter alia, active engaged participation.

Attitude, behavior and practice of primary school students with regard to soil transmitted helminths in Grenada

OBJECTIVE: To identify the attitude, behaviour and practice of parents, guardians and adolescents associated with Soil Transmitted Helminth’s (STH’s). DESIGN AND METHODS: A questionnaire was completed by 811 parents /guardians. The questionnaire posed questions on the socio economic, attitudes, behavior and practices of primary school students with regard to factors that could contribute to the transmission of STH’s in Grenada. RESULTS: 534 (66%) parents/guardian reported that their children regularly washed their hands before eating, 690 (85%) had an inside water supply, 465 (57%) had indoor toilets. Also, 579 (71%) said that their children never played around outdoor latrines and 326 (40%) said their children always wore shoes outdoors. 732 (90%) of the parents/guardians reported that vegetables and fruits were always washed before cooking and 662 (82%) said that their children had previously received de-worming medication. CONCLUSION: Practical recommendations such as in-house sanitation facilities and hand washing programs can be made. This will enable limited resources to be used more efficiently to combat the problem of transmission of STH’s.

Modified informed consent in a viral seroprevalence study in the Caribbean.

An unlinked seroprevalence study of HIV and other viruses was conducted on pregnant women on the Caribbean island of Grenada in 1994. Investigators were from both the developed world and the Grenadian Ministry of Health (MOH). There was then no board on Grenada to protect research subjects or review ethical aspects of studies. Nurses from the MOH were asked to verbally inform their patients about the study, and request that patients become subjects of the study and give blood for screening. If consent was given nurses took blood and administered a survey about each subjects' knowledge of HIV transmission routes. Nurses shared a spoken dialect and cultural heritage with prospective subjects and were probably more effective than foreign researchers at informing subjects. Informed consent was obtained with a simplified consent form supplemented with conversation with each prospective research subject. Facilitating discussion between people with common cultural backgrounds helps apply the Western approach to informed consent to communites in the developing world. Researchers must disclose all information to nurses or other mediators, and ensure that nurses disclose as much information as possible to prospective subjects. So modified, informed consent maintains respect for persons and becomes applicable and relevant to various cultures.