Serotype distribution, virulence and antibiotic resistance of Streptococcus agalactiae isolated from cultured tilapia Oreochromis niloticus in Lake Volta, Ghana.

Streptococcus agalactiae infection is one of the major factors limiting the expansion of tilapia farming globally. In this study, we investigated the serotype distribution, virulence and antimicrobial resistance of S. agalactiae isolates from tilapia farmed in Lake Volta, Ghana. Isolates from 300 moribund fish were characterised by Gram staining, MALDI-TOF/MS and 16S rRNA sequencing. Serotype identification was based on multiplex polymerase chain reaction (PCR) amplification of the capsular polysaccharide genes. Detection of virulence genes (cfb, fbsA and cspA) and histopathology were used to infer the pathogenicity of the isolates. The susceptibility of isolates to antibiotics was tested using the Kirby-Bauer disk diffusion assay. All 32 isolates identified as S. agalactiae were of serotype Ia. This was notably different from isolates previously collected from the farms in 2017, which belonged to serotype Ib, suggesting a possible serotype replacement. The prevalence of the pathogen was related to the scale of farm operation, with large-scale farms showing higher S. agalactiae positivity. Data from histopathological analysis and PCR amplification of targeted virulence genes confirmed the virulence potential and ability of the isolates to cause systemic infection in tilapia. Except for gentamicin, the majority of the isolates were less resistant to the tested antibiotics. All isolates were fully sensitive to oxytetracycline, erythromycin, florfenicol, enrofloxacin, ampicillin and amoxicillin. This study has improved our understanding of the specific S. agalactiae serotypes circulating in Lake Volta and demonstrates the need for continuous monitoring to guide the use of antimicrobials and vaccines against streptococcal infections in Ghanaian aquaculture systems.

Hepatitis B and human immunodeficiency virus infections within correctional facilities in Ghana.

Previous studies have suggested high Immunodeficiency Virus (HIV) and hepatitis B virus (HBV) prevalence in prisons in Ghana. However, this study was part of a nationally representative bio-behavioural survey and determined the prevalence of HIV and HBV among prison inmates and identified factors associated with these infections. Both biomedical and behavioural data were collected from a total of 2,443 prison inmates from 19 prison stations during 2013 in Ghana; 12 male prisons and 7 female prisons selected across the country. The national HIV screening algorithm was used for HIV testing while two rapid detection tests were used to confirm HBV infections. HIV and HBV prevalence among prisoners in Ghana were approximately 2.34% and 12.38% respectively. Only 5 inmates, had co-infection with both viruses. The prevalence of HIV was significantly lower among male inmates (1.5%) compared to the female inmates (11.8%). Age, sex, and marital status, were significantly associated with both HIV and HBV infections. However, BMI category, IDU, and time spent in prison were associated with HIV infections. The educational level was significantly associated with HBV infections. After binary logistic regression, being female (AOR: 0.18, 95% CI: 0.07-0.45, p<0.001) and having a stay of 5 years or more (AOR: 0.07, 95% CI: 0.01-0.60, p = 0.016), increased the risk of having HIV infection. While, those with no formal education (AOR: 0.65, 95% CI: 0.45-0.95, p = 0.024) and are underweight (AOR: 0.51, 95% CI: 0.27-0.99, p = 0.046), were more likely to have HBV infection. Forced penetrative sex may be a problem in the prisons. The need to have and strengthen an integrated screening, treatment and vaccination plan for the prison is emphasized. The prison does not serve as an exceptionally high risk to the general population. The findings support a critical look at the issue of forced penetrative sex in the prisons.