Cross-sectional prospective feasibility study of newborn screening for sickle cell anaemia and congenital hypothyroidism in Guyana.

INTRODUCTION: Newborn screening (NBS) is a test done shortly after birth to detect conditions that cause severe health problems if not treated early. An estimated 71% of babies worldwide are born in jurisdictions that do not have an established NBS programme. Guyana currently has no NBS programme and has established a partnership with Newborn Screening Ontario (NSO) to initiate screening. OBJECTIVES: To assess the feasibility of implementing a NBS programme in Guyana for congenital hypothyroidism (CH) and haemoglobinopathies (HBG) and to report on screen positive rates and prevalence (Hardy-Weinberg equilibrium (HWE)) for CH and HBG. METHODS: Term, healthy Guyanese infants were evaluated (with consent) using heel prick dried blood spots (DBS) shortly after birth (closer to 24 hours of life). DBS samples were analysed at NSO. Screening test for CH was done using a human thyroid-stimulating hormone (hTSH) assay. Mean hTSH levels between the Guyanese sample and the Ontarian population were compared using Student's t-test with an alpha of 0.05. Screening test for HBG was performed with a cation-exchange high-performance liquid chromatography. RESULTS: The pilot was conducted from 6 June 2016 to 22 September 2017. Georgetown Public Hospital Corporation recruited 2294 mothers/infants. Screen positive rate for CH in our sample was 0.0% (0/2038 infants). Mean TSH levels in Guyanese samples (1.7 µU/mL blood) was noticed to be significantly different than in the Ontarian population (4.3 µU/mL blood) (p<0.05). Screen positive rate for sickle cell anaemia (SCA) in our sample was 0.3% (7/2039 patients), and the carrier rate was 8.4% (172/2039 patients). Using the HWE, the SCA frequency (S allele frequency)2 is 0.0492=0.002 CONCLUSION: NBS for CH and SCA in Guyana could be beneficial. Future work should focus on conducting larger pilots which could be used to inform diagnosis and treatment guidelines for Guyanese people.

Prevalence and molecular characteristics of methicillin-resistant Staphylococcus aureus among skin and soft tissue infections in an emergency department in Guyana.

OBJECTIVE: The characteristics of staphylococcal skin and soft tissue infections (SSTIs) are poorly understood in northern South America and the Caribbean. The objectives of this study were to determine the frequency of methicillin resistance among Staphylococcus aureus isolates in an emergency department (ED) in Guyana and to identify specific molecular characteristics of these methicillin-resistant Staphylococcus aureus (MRSA) strains. METHODS: This was a cross-sectional study conducted at the main teaching hospital in Georgetown, Guyana. Eligible subjects included patients of all ages with SSTIs with obtainable purulent material. Purulent material was cultured, and S. aureus isolates were evaluated for antibiotic susceptibilities by disc diffusion. Molecular characterisation of MRSA isolates included identification of SCCmec type, assignment of genetic relatedness by rep-PCR and determination of the presence of two exotoxins, Panton-Valentine Leukocidin (PVL) and LukAB. RESULTS: Eighty-five samples were collected; of these, 47 grew S. aureus. 24 of the 47 S. aureus samples were MRSA (51%; 95% CI 37% to 65%), representing 28% of all samples. All MRSA isolates were SCCmec type IV, PVL positive, LukAB positive and were highly related to the current epidemic clone in the USA, USA300. CONCLUSIONS: Here, we demonstrate a clinically significant proportion of methicillin resistance in SSTI-associated staphylococcal isolates. Guyanese isolates were highly related to the most common community-associated strain seen in the USA, USA300. These results have important implications for empiric antibiotic therapy and infection control policies in Guyana and similar settings.

Determining the community prevalence of acute gastrointestinal illness and gaps in surveillance of acute gastroenteritis and foodborne diseases in Guyana.

Guyana is an English-speaking country in South America and, culturally, it is part of the Caribbean. Objective of this study was to determine the community prevalence and true burden and economic impact of acute gastroenteritis (AGE) and foodborne diseases (FBDs) in Guyana. A cross-sectional population-based survey was conducted in 7 of the 10 regions in Guyana during August and November 2009 to capture the high- and low-AGE season respectively. Overall, 1,254 individual surveys were administered at a response rate of 96.5%. The overall monthly prevalence of self-reported cases of AGE was 7.7% (97 cases) (95% CI 6.3-9.3), and the yearly incidence was 1.0 episodes per person-year. The highest monthly prevalence of AGE was observed in region 4 (8.9%) and in children aged 1-4 year(s) (12.7%). Of the 97 AGE cases, 23% sought medical care; 65% reported spending time at home due to their illness [range 1-20 day(s), mean 2.7 days], of whom 51% required other individuals to look after them while ill. The maximum number of stools per 24 hours ranged from 3 to 9 (mean 4.5), and number of days an individual suffered from AGE ranged from 1 to 21 day(s) (mean 2.7 days). The burden of syndromic AGE cases in the population for 2009 was estimated to be 131,012 cases compared to the reported 30,468 cases (76.7% underreporting), which implies that, for every syndromic case of AGE reported, there were additional 4.3 cases occurring in the community. For every laboratory-confirmed case of FBD/AGE pathogen reported, it was estimated that approximately 2,881 more cases were occurring in the population. Giardia was the most common foodborne pathogen isolated. The minimum estimated annual cost associated with the treatment for AGE was US$ 2,358,233.2, showing that AGE and FBD pose a huge economic burden on Guyana. Underreporting of AGE and foodbome pathogens, stool collection, and laboratory capacity were major gaps, affecting the surveillance of AGE in Guyana.

Leptospirosis outbreak following severe flooding: a rapid assessment and mass prophylaxis campaign; Guyana, January-February 2005.

BACKGROUND: Leptospirosis is a zoonosis usually transmitted through contact with water or soil contaminated with urine from infected animals. Severe flooding can put individuals at greater risk for contracting leptospirosis in endemic areas. Rapid testing for the disease and large-scale interventions are necessary to identify and control infection. We describe a leptospirosis outbreak following severe flooding and a mass chemoprophylaxis campaign in Guyana. METHODOLOGY/PRINCIPAL FINDINGS: From January-March 2005, we collected data on suspected leptospirosis hospitalizations and deaths. Laboratory testing included anti-leptospiral dot enzyme immunoassay (DST), immunohistochemistry (IHC) staining, and microscopic agglutination testing (MAT). DST testing was conducted for 105 (44%) of 236 patients; 52 (50%) tested positive. Four (57%) paired serum samples tested by MAT were confirmed leptospirosis. Of 34 total deaths attributed to leptospirosis, postmortem samples from 10 (83%) of 12 patients were positive by IHC. Of 201 patients interviewed, 89% reported direct contact with flood waters. A 3-week doxycycline chemoprophylaxis campaign reached over 280,000 people. CONCLUSIONS: A confirmed leptospirosis outbreak in Guyana occurred after severe flooding, resulting in a massive chemoprophylaxis campaign to try to limit morbidity and mortality.