Dr Bernice N Harris
@up.ac.za
Senior Lecturer, School of Health Systems and Public Health, Health Scences Faculty
University of Pretoria
RESEARCH, TEACHING, or OTHER INTERESTS
Multidisciplinary, Infectious Diseases, Public Health, Environmental and Occupational Health, Epidemiology
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Francis B. Kolo, Abiodun A. Adesiyun, Folorunso O. Fasina, Bernice N. Harris, Jennifer Rossouw, Charles Byaruhanga, Hermanus De Wet Geyer, Lucille Blumberg, John Frean, and Henriette van Heerden
MDPI AG
Abattoir workers are liable to zoonotic infections from animals and animal products, primarily to diseases with asymptomatic and chronic clinical manifestations in animals, such as brucellosis. No published reports exist on the seroprevalence of brucellosis in abattoir workers in South Africa. Therefore, this cross-sectional study was conducted to estimate the occurrence and risk factors for Brucella exposure in abattoir workers in Gauteng Province. A total of 103 abattoir workers and managers from 6 abattoirs, where brucellosis-positive slaughtered cattle and sheep were previously detected, were interviewed and tested with serological assays using the Rose Bengal test (RBT), BrucellaCapt, and IgG-ELISA. A pre-tested questionnaire was administered to consenting respondents to obtain information on risk factors for brucellosis. Of the 103 respondents tested, the distribution of female and male workers was 16 (15.5%) and 87 (84.5%), respectively. The seroprevalence for exposure to brucellosis was 21/103 (20.4%, 95%CI: 13.1–29.5) using a combination of RBT, BrucellaCapt, or IgG-ELISA. For test-specific results, seroprevalences by RBT, BrucellaCapt, and IgG-ELISA were 13/103 (12.6%, 95%CI: 6.9–20.6), 9/103 (8.74%, 95%CI: 4.1–15.9), and 18/103 (17.5%, 95%CI: 10.7–26.2), respectively. Low-throughput abattoirs were identified as associated risks, as 29.3% of workers were seropositive compared with 12.7% of workers in high-throughput abattoirs, which highlights that direct contact at abattoirs poses higher risk to workers than indirect and direct contact outside abattoirs. This study confirms the occurrence of Brucella spp. antibodies among abattoir workers in South Africa, possibly due to occupational exposure to Brucella spp., and highlights the occupational hazard to workers. Furthermore, findings underscore that abattoir facilities can serve as points for active and passive surveillance for indicators of diseases of public health importance. We recommend periodic implementation of brucellosis testing of abattoir workers country-wide to establish baseline data for informing appropriate preventive practices and reducing the potential burden of infection rates among these high-risk workers.
Sean M. Patrick, Marc-Karim Bendiane, Taneshka Kruger, Bernice N. Harris, Megan A. Riddin, Helene Trehard, Christiaan de Jager, Riana Bornman, and Jean Gaudart
Springer Science and Business Media LLC
Abstract Background Over the past decade, implementation of multiple malaria control strategies in most countries has largely contributed to advance the global malaria elimination agenda. Nevertheless, in some regions, seasonal epidemics may adversely affect the health of local populations. In South Africa, Plasmodium falciparum malaria is still present, with the Vhembe District experiencing an incidence rate of 3.79 cases/1000 person-years in 2018, particularly in the Limpopo River Valley, bordering Zimbabwe. To elucidate the complexity of the mechanisms involved in local regular malaria outbreaks, a community-based survey was implemented in 2020 that focused on the relationship between housing conditions and malaria risky behaviours. Methods The community-based cross-sectional survey was conducted among the population of three study sites in the Vhembe District, which were selected based on malaria incidence rate, social and health characteristics of inhabitants. The household survey used a random sampling strategy, where data were collected through face-to-face questionnaires and field notes; to described the housing conditions (housing questionnaire), and focus on individual behaviours of household members. Statistical analyses were performed combining hierarchical classifications and logistic regressions. Results In this study, 398 households were described, covering a population of 1681 inhabitants of all ages, and 439 adults who participated in community-based survey. The analysis of situations at risk of malaria showed that the influence of contextual factors, particularly those defined by the type of habitat, was significant. Housing conditions and poor living environments were factors of malaria exposure and history, regardless of site of investigation, individual preventive behaviours and personal characteristics of inhabitants. Multivariate models showed that, considering all personal characteristics or behaviours of inhabitants, housing conditions such as overcrowding pressures were significantly associated with individual malaria risk. Conclusions The results showed the overwhelming weight of social and contextual factors on risk situations. Considering the Fundamental Causes Theory, malaria control policies based on health behaviour prevention, should reinforce access to care or promoting health education actions. Overarching economic development interventions in targeted geographical areas and populations have to be implemented, so that malaria control and elimination strategies can be efficiently and effectively managed.
Susan C. Aitken, Samanta T. Lalla-Edward, Maren Kummerow, Stan Tenzer, Bernice N. Harris, W. D. Francois Venter, and Alinda G. Vos
MDPI AG
Cardiovascular disease (CVD) is the leading cause of death globally. The occupational challenges of bus drivers may increase their risk of CVD, including developing obesity, hypertension, and diabetes. We evaluated the medical records of 266 bus drivers visiting an occupational medical practice between 2007 and 2017 in Johannesburg, South Africa, to determine the health status of bus drivers and investigate risk factors for CVD, and their impact on the ability to work. The participants were in majority male (99.3%) with a median age of 41.2 years (IQR 35.2); 23.7% were smokers, and 27.1% consumed alcohol. The median body mass index (BMI) was 26.8 m/kg2 (IQR 7.1), with 63.1% of participants having above normal BMI. Smoking, BMI, and hypertension findings were in line with national South African data, but diabetes prevalence was far lower. Undiagnosed hypertension was found in 9.4% of participants, uncontrolled hypertension in 5.6%, and diabetes in 3.0%. Analysis by BMI category found that obesity was significantly associated with increased odds of hypertension. Uncontrolled hypertension was the main reason for being deemed ‘unfit to work’ (35.3%). Our research highlights the need for more regular screening for hypertension and interventions to address high BMI.
Krpasha Govindasamy, Peter N. Thompson, Bernice N. Harris, Jennifer Rossouw, Darrell A. Abernethy, and Eric M. C. Etter
MDPI AG
In South Africa, the prevalence of cattle handler exposure to Brucella on cattle farms is unknown and risk factors and cattle symptoms associated with infected cattle herds are unavailable. To address this gap, a case-control study of cattle herds was conducted in Gauteng province and farm workers and veterinary officials were tested for exposure to Brucella. Seroprevalence amongst farm workers exposed to case herds ranged from 4.0% (BrucellaCapt®) to 16.7% (IgG ELISA®), compared to those exposed to control herds, where seroprevalence ranged from 1.9% (BrucellaCapt®) to 5.7% (IgG ELISA®). Seroprevalence amongst veterinary officials was significantly greater compared to farm workers exposed to case herds for the outcome RBT+ IgM- IgG+ (OR = 11.1, 95% CI: 2.5–49.9, p = 0.002) and RBT- IgM- IgG+ (OR = 6.3, 95% CI: 2.3–17.3, p < 0.001). Risk factors associated with being an infected herd were: being a government-sponsored farm vs. private farm (OR 4.0; 95% CI: 1.4–11.3; p = 0.009), beef vs. dairy herd (OR 7.9; 95% CI: 1.4–44.9; p = 0.020), open vs. closed herd (OR 3.3; 95% CI: 1.1–10.4; p = 0.038) and the presence of antelope on the farm (OR 29.4; 95% CI: 4.0–218.2; p = 0.001). Abortions (OR = 5.1; 95% CI: 2.0–13.3; p < 0.001), weak calves in the herd (OR = 8.0; 95% CI: 2.6–24.4; p < 0.001), reduction in number of calves born (OR = 9.0; 95% CI: 2.1–43.6; p < 0.001), reduction in conception rate (OR = 3.9; 95% CI: 0.8–18.3; p = 0.046), hygromas in cattle (p = 0.011) and farmers reporting brucellosis-like symptoms in their farm workers or in him/herself (OR = 3.4; 95% CI: 1.3–8.7; p = 0.006) were more likely to be associated with Brucella infected herds than control herds. This evidence can be used in strategic planning to protect both human and herd health.
Krpasha Govindasamy, Eric M. C. Etter, Bernice N. Harris, Jennifer Rossouw, Darrell A. Abernethy, and Peter N. Thompson
MDPI AG
Brucellosis in humans is under-detected and underreported in sub-Saharan Africa. Risk factors associated with Brucella infection and health seeking behaviour in response to brucellosis-like symptoms, amongst cattle farm workers and veterinary officials in South Africa, are unknown. Farm workers and veterinary officials (N = 230) were screened for brucellosis using commercial Rose Bengal Test (RBT®), IgM Enzyme-linked Immunoassay (ELISA)®, IgG ELISA® and the BrucellaCapt® test. Knowledge of brucellosis and risk factors for exposure to Brucella were also investigated. Seroprevalence varied according to test used: 10.1% (RBT®), 20.9% (IgG ELISA®) and 6.5% (BrucellaCapt®). Only 22.2% (6/27) of veterinary officials opt to visit a clinic, doctor, or hospital in response to self-experienced brucellosis-like symptoms, compared to 74.9% (152/203) of farm workers (p < 0.001). Of the BrucellaCapt® seropositive participants, 53% (7/15) did not visit a clinic in response to brucellosis-like symptoms. Weak evidence of an association between the handling of afterbirth or placenta and infection of a short evolution (RBT®, IgM ELISA® and IgG ELISA® seropositive) was found (OR = 8.9, 95% CI: 1.0–81.1, p = 0.052), and strong evidence of an association between this outcome and the slaughter of cattle (OR = 5.3, 95% CI: 1.4–19.6, p = 0.013). There was strong evidence of a positive association between inactive/resolved infection and veterinary officials vs. farm workers exposed to seropositive herds (OR = 7.0, 95% CI: 2.4–20.2, p < 0.001), with a simultaneous negative association with the handling of afterbirth or placenta (OR = 3.9, 95% CI: 1.3–11.3, p = 0.012). Findings suggest a proportion of undetected clinical cases of brucellosis amongst workers on cattle farms in Gauteng.
N R Gloeck, B N Harris, E M Webb, and A Scheibe
South African Medical Association NPC
BACKGROUND
In South Africa (SA), increasing illicit opioid use and associated health challenges can be managed with opioid substitution therapy (OST), such as methadone, if the recommended dose and duration of use are prescribed. The Community Oriented Substance Use Programme (COSUP) provides free methadone to patients with opioid use disorder in Tshwane, SA, on need-based criteria.
OBJECTIVES
To determine selected sociodemographic and substance use treatment factors associated with retention for at least 6 months among participants receiving methadone as part of OST in COSUP.
METHODS
This was a retrospective cohort study using secondary data of patients treated with methadone at 8 COSUP sites. The factors associated with at least 6 months' retention for 575 participants from December 2016 to September 2018 were analysed.
RESULTS
There were 91.3% males, 86.4% South Africans and 85.9% black Africans, with a median age of 30 years. At baseline, the majority were injecting heroin (55.5%) and were provided with free methadone (59.3%). The median dose of methadone at 6 months or on leaving the programme was 20 mg; 38.4% of participants were retained for at least 6 months. Of those not retained, the median duration on methadone was 56 days, whereas for those retained for at least 6 months, the median number of days on methadone were 254. After adjusting for sex and age, participants receiving methadone doses <50 mg had lower odds of being retained (0 - 20 mg: adjusted odds ratio (aOR) 0.25; p=0.002; 95% confidence interval (CI) 0.10 - 0.61; >20 - 40 mg: aOR 0.20; p<0.001; 95% CI 0.08 - 0.49) than those administered ≥50 mg. Participants who received free methadone had 3.75 the odds of being retained than those buying it themselves (p<0.001; 95% CI 2.47 - 5.70). Participants treated in the inner city had 5.19 the odds of being retained than those in a suburban setting (p<0.001; 95% CI 2.99 - 9.03). Compared with black African participants, white participants had 3.39 the odds of being retained (p=0.001; 95% CI 1.64 - 7.00). Injecting heroin users had 0.63 the odds of being retained (p=0.032; 95% CI 0.41 - 0.96).
CONCLUSIONS
To maximise retention on OST, methadone should be free, with maintenance doses >50 mg. Reasons for lower retention among participants from periurban settings, those who inject and those from previously disadvantaged racial groups need to be explored, and findings used to inform programming.
Cheryl M.E. McCrindle, Solly N. Manoto, and Bernice Harris
Medpharm Publications
Bovine brucellosis affects food safety, food security and human health in rural communities in the North West Province, South Africa. The World Organisation for Animal Health suggests routine sero-surveillance and vaccination of cattle for control and to prevent zoonotic transmission. Although sero-surveillance and subsidised vaccination have been in place for decades, data from Bojanala have not previously been analysed. The aim of this study was to retrospectively analyse historical data on routine sero-surveillance of bovine brucellosis and state subsidised vaccination, in communal, commercial and dairy cattle in the study area. This was a descriptive, cross-sectional retrospective analysis of records from all adult cows bled by the state veterinary services during routine sero-surveillance for bovine brucellosis, in the Bojanala Region, North West Province, between 2009 and 2013. Fewer communal (N = 11 815) and dairy (N = 6696), than commercial beef (N = 28 251) cows, were tested. Overall herd prevalence (33.33%), differed significantly from individual prevalence (3.18%) in all groups. Communal herds had both the highest herd prevalence (38.8%) and the highest individual prevalence (5.2%). Both herd and individual sero-prevalence were lowest in dairy cattle, possibly because registered dairy herds are routinely tested. Over the 5-year study period, only 24 086 (7.15%) of the 342 500 cows eligible for free vaccination, were vaccinated. The annual number of cattle tested was highly variable. Dairy cattle that were regularly tested had a significantly lower herd and individual prevalence. Herd prevalence would be useful for spatial mapping, whilst individual prevalence could better reflect the risk of zoonotic transmission.
Genevie M. Ntshoe, Johanna M. McAnerney, Stefano Tempia, Lucille Blumberg, Jocelyn Moyes, Amelia Buys, Dhamari Naidoo, Marietjie Venter, Terry Besselaar, Barry D. Schoub,et al.
Public Library of Science (PLoS)
Background There is limited data on the epidemiology of influenza and few published estimates of influenza vaccine effectiveness (VE) from Africa. In April 2009, a new influenza virus strain infecting humans was identified and rapidly spread globally. We compared the characteristics of patients ill with influenza A(H1N1)pdm09 virus to those ill with seasonal influenza and estimated influenza vaccine effectiveness during five influenza seasons (2005–2009) in South Africa. Methods Epidemiological data and throat and/or nasal swabs were collected from patients with influenza-like illness (ILI) at sentinel sites. Samples were tested for seasonal influenza viruses using culture, haemagglutination inhibition tests and/or polymerase chain reaction (PCR) and for influenza A(H1N1)pdm09 by real-time PCR. For the vaccine effectiveness (VE) analysis we considered patients testing positive for influenza A and/or B as cases and those testing negative for influenza as controls. Age-adjusted VE was calculated as 1-odds ratio for influenza in vaccinated and non-vaccinated individuals. Results From 2005 through 2009 we identified 3,717 influenza case-patients. The median age was significantly lower among patients infected with influenza A(H1N1)pdm09 virus than those with seasonal influenza, 17 and 27 years respectively (p<0.001). The vaccine coverage during the influenza season ranged from 3.4% in 2009 to 5.1% in 2006 and was higher in the ≥50 years (range 6.9% in 2008 to 13.2% in 2006) than in the <50 years age group (range 2.2% in 2007 to 3.7% in 2006). The age-adjusted VE estimates for seasonal influenza were 48.6% (4.9%, 73.2%); −14.2% (−9.7%, 34.8%); 12.0% (−70.4%, 55.4%); 67.4% (12.4%, 90.3%) and 29.6% (−21.5%, 60.1%) from 2005 to 2009 respectively. For the A(H1N1)pdm09 season, the efficacy of seasonal vaccine was −6.4% (−93.5%, 43.3%). Conclusion Influenza vaccine demonstrated a significant protective effect in two of the five years evaluated. Low vaccine coverage may have reduced power to estimate vaccine effectiveness.
Genevie M. Ntshoe, Johanna M. McAnerney, Brett N. Archer, Sheilagh B. Smit, Bernice N. Harris, Stefano Tempia, Mirriam Mashele, Beverley Singh, Juno Thomas, Ayanda Cengimbo,et al.
Public Library of Science (PLoS)
Background Since 1995, measles vaccination at nine and 18 months has been routine in South Africa; however, coverage seldom reached >95%. We describe the epidemiology of laboratory-confirmed measles case-patients and assess the impact of the nationwide mass vaccination campaign during the 2009 to 2011 measles outbreak in South Africa. Methods Serum specimens collected from patients with suspected-measles were tested for measles-specific IgM antibodies using an enzyme-linked immunosorbent assay and genotypes of a subset were determined. To estimate the impact of the nationwide mass vaccination campaign, we compared incidence in the seven months pre- (1 September 2009–11 April 2010) and seven months post-vaccination campaign (24 May 2010–31 December 2010) periods in seven provinces of South Africa. Results A total of 18,431 laboratory-confirmed measles case-patients were reported from all nine provinces of South Africa (cumulative incidence 37 per 100,000 population). The highest cumulative incidence per 100,000 population was in children aged <1 year (603), distributed as follows: <6 months (302/100,000), 6 to 8 months (1083/100,000) and 9 to 11 months (724/100,000). Forty eight percent of case-patients were ≥5 years (cumulative incidence 54/100,000). Cumulative incidence decreased with increasing age to 2/100,000 in persons ≥40 years. A single strain of measles virus (genotype B3) circulated throughout the outbreak. Prior to the vaccination campaign, cumulative incidence in the targeted vs. non-targeted age group was 5.9-fold higher, decreasing to 1.7 fold following the campaign (P<0.001) and an estimated 1,380 laboratory-confirmed measles case-patients were prevented. Conclusion We observed a reduction in measles incidence following the nationwide mass vaccination campaign even though it was conducted approximately one year after the outbreak started. A booster dose at school entry may be of value given the high incidence in persons >5 years.
K. H. KEDDY, A. SOOKA, H. ISMAIL, A. M. SMITH, I. WEBER, M. E. LETSOALO, and B. N. HARRIS
Cambridge University Press (CUP)
SUMMARYIn 2005, over 600 clinically diagnosed typhoid fever cases occurred in South Africa, where an outbreak had been previously described in 1993. Case-control and molecular investigations, including Salmonella enterica serovar Typhi (S. Typhi) isolates from that area from 1993, 2005 and later, were undertaken. Controls were significantly older than cases (P=0·003), possibly due to immunity from previous infection, and a significantly larger proportion had attended a gathering (P=0·035). Exposure to commercial food outlets and person-to-person transmission was not significant. Pulsed-field gel electrophoresis and multi-locus tandem repeat analysis revealed common clusters of S. Typhi strains identified in 1993 and 2005 as well as in 2007 and 2009. This outbreak probably occurred in a non-immune population due to faecally contaminated water. S. Typhi strains appeared to be related to strains from 1993; failure to address unsafe water may lead to further outbreaks in the area if the current population immunity wanes or is lost.
Bernice N Harris, David N Durrheim, and Gboyega A Ogunbanjo
Wiley
A major pre‐requisite for polio‐free certification by the World Health Organization is that the local surveillance system successfully detects one case of non‐polio acute flaccid paralysis (AFP) per 100 000 children below 15 years of age per annum and that no cases of polio occur for three consecutive years. Mpumalanga, a rural province in the northeast of South Africa, implemented an enhanced surveillance system, which consisted of training hospital ICNs to rapidly report and correctly respond to nine infectious disease syndromes, including AFP. Weekly zero reporting is a component of the system. The non‐polio AFP reporting rate per 100 000 children below the age of 15 years increased from 0.56 in 1997 to 0.91 in 1998 after introduction of the enhanced surveillance system, with more than 80% of the units reporting weekly. All units reported weekly from April 1999 to December 2001. Although non‐polio AFP reporting rates were 0.27 (1999), 1.18 (2000) and 0.87 (2001), the 95% binomial exact confidence intervals for all years included 1 per 100 000. A review of paediatric admissions from January 1998 to December 2001 at all hospitals revealed that only five AFP cases had been missed by the enhanced surveillance system. The low international AFP reference rate and attendant variation expected due to chance, particularly in areas with relatively small populations, is an important factor that deserves more attention as we approach global polio eradication.
A. Uzicanin
Oxford University Press (OUP)
BACKGROUND
In South Africa, as part of an effort to eliminate indigenous measles by 2002, vaccination campaigns were conducted in 1996-1997 targeting all children aged 9 months to 14 years; coverage was estimated at 85%. The impact of the campaigns on measles disease burden was evaluated in 1999.
METHODS
We analysed routine measles surveillance data and undertook a retrospective review of hospital registers in two of South Africa's nine provinces.
RESULTS
In Mpumalanga in the pre-campaign years (1992-1996), 4,498 measles cases and 6 deaths were reported; 182 cases and no deaths were reported in 1997-1998. Hospital registers showed 1,647 measles hospitalizations and 11 deaths in the pre-campaign period, and 60 hospitalizations and no deaths after the campaign (1997-April 1999). In Western Cape in pre-campaign years (1992-1997), 5,164 measles cases and 19 deaths were reported; 132 cases and no deaths were reported in 1998. Hospital registers showed 736 measles hospitalizations and 23 deaths in the pre-campaign period, and 29 measles hospitalizations and no deaths post-campaign (1998-July 1999).
CONCLUSIONS
Study findings indicate that reported measles cases, measles-related hospitalizations and deaths were considerably reduced in both provinces after the campaign compared with the pre-campaign period. Longer observation is needed to evaluate the long-term impact of the campaigns.
C. D. Idema, B. N. Harris, G. A. Ogunbanjo, and D. N. Durrheim
Wiley
Neonatal tetanus (NNT) is a serious but preventable disease, and the World Health Organization (WHO) wants to eliminate NNT globally by reducing its incidence to <1 case per 1000 live births. South Africa adopted this goal in 1995, but Mpumalanga, a rural province, has consistently reported cases of NNT despite an appropriate vaccination strategy to eliminate the disease. The aim of the study was to investigate the completeness of the passive notification system and to explore reasons for ongoing NNT cases despite implementation of the provincial vaccination strategy. We reviewed all hospital admissions in the province between 1996 and 2000 meeting the case definition for NNT and interviewed mothers of the NNT cases reported in 2000. We identified 26 NNT cases, of which only 14 (54%) were reported through the routine notification system. Most cases occurred as a result of the cultural practice of applying cow dung or rat faeces to the umbilical stump in the neonatal period. Although all districts met the WHO elimination target during the review period, there is scope to prevent unnecessary NNT deaths through culturally acceptable public awareness campaigns aimed at changing harmful practices, and encouraging hygienic births and postnatal cord care.
M. B. Taylor, P. J. Becker, E. Janse Van Rensburg, B. N. Harris, I. W. Bailey, and W. O. K. Grabow
Cambridge University Press (CUP)
SummaryCertain health risks have been associated with recreational exposure to faecally polluted water. Canoeing in certain South African waters is considered to be a high risk activity with regard to schistosomiasis. gastroenteritis and possibly hepatitis. In a cross-sectional study, a serosurvey was conducted amongst canoeists to ascertain whether or not they had a higher seroprevalence to hepatitis A virus. Norwalk virus andSchistosomaspp. than non-canoeists. In comparisons between the two groups, a significant association could not be demonstrated between canoeing and antibody response to hepatitis A and Norwalk viruses (P-values for age-adjustedχ2were 0·083 and 0·219 respectively), but a significant association could be demonstrated between canoeing and the antibody response to Schistosoma spp. (P> 0·001: age-adjusted).