Search PubMed⌕ Search

Biomedical subjects

David Mabey

Publications and source records attributed to David Mabey.

At least 19 recordsLinked to original sources
PubMed2006

Intensive insecticide spraying for fly control after mass antibiotic treatment for trachoma in a hyperendemic setting: a randomised trial.

BACKGROUND: There are no data on the cumulative effect of fly control and antibiotic distribution on trachoma in hyperendemic communities. We sought to determine whether insecticide spray intervention after mass antibiotic treatment could reduce trachoma and ocular infection with Chlamydia trachomatis in hyperendemic neighbourhoods in Tanzania. METHODS: We did a single-blind, randomised clinical trial in 16 neighbourhoods (balozi) in Kongwa, Tanzania. All children aged 1-7 years were enrolled, with 119 children in the eight balozi of the intervention group and 183 in the eight control balozi. Children were examined at baseline, 6 months, and 1 year for clinical trachoma and ocular C trachomatis infection. One dose of azithromycin was offered to all residents of both intervention and control balozi after the baseline survey. Households (and surrounding areas) in the intervention group were then sprayed with insecticide throughout the ensuing year and monitored for reductions in fly counts. This study is registered at ClinicalTrials.gov, number NCT00347763. FINDINGS: The intervention balozi had significantly lower fly counts than controls at all monitored weeks (p<0.05), apart from weeks 7-9. The trachoma rate did not differ significantly in the intervention and control balozi at 6 months post-treatment (20%vs 33%, p=0.07), nor did it at 1 year (43%vs 44%, p=0.90). Infection with C trachomatis did not differ between groups at 6 months post-treatment (9%vs 7%, p=0.45). INTERPRETATION: Intensive insecticide spraying reduced flies in the environment, but our results suggest that fly reduction after mass antibiotic treatment has no added benefit on reduction of trachoma.

Anti-Bacterial Agents↗
PubMed2006

The relationship between prevalence of active trachoma, water availability and its use in a Tanzanian village.

This study aimed to establish the relationship between the prevalence of active trachoma in children, water availability and household water use in a village in Tanzania. Nine hundred and fourteen children aged 1-9 years were examined for signs of trachoma. Data were collected on time taken to collect water, amount of water collected and other trachoma risk factors. In a sub-study, 99 randomly selected households were visited twice daily on two consecutive days to document patterns of water use. The prevalence of active trachoma in the children examined was 18.4% (95% CI 15.9-20.9). Active trachoma prevalence increased with increasing water collection time (OR 2.25; 95% CI 1.13-4.46) but was unrelated to the amount of water collected. In the sub-study, active trachoma prevalence was substantially lower in children from households where more water was used for personal hygiene (P for trend < or =0.01), independent of the total amount of water used. The allocation of water to hygiene was predicted by lower water collection time. The key element in the relationship between water availability and trachoma is the allocation of water within households. Collection time may influence both the quantity of water collected and its allocation within the household.

Child↗
PubMed2006

Mapping the global distribution of trachoma.

OBJECTIVE: We aimed to summarize and map the existing global population-based data on active trachoma and trichiasis. Detailed distribution maps of various infectious diseases have proved a valuable tool in their control. Such maps play an important role in assessing the magnitude of the problem, defining priority areas for control, monitoring changes, and advocacy. Until now, information on trachoma prevalence at within country levels has not been systematically collated, analysed and reported. METHODS: We gathered the last 18 years' worth of reported data on active trachoma in children aged less than 10 years, and the last 25 years of reported trichiasis in adults aged 15 years and over from 139 population-based surveys in 33 countries. We collated these data into one database using the "district" (second administrative level) as the standard unit of reporting. We used Geographical Information Systems as a database and cartographic tool to generate a global map of the prevalence of trachoma and trichiasis. FINDINGS: We obtained data on active trachoma and trichiasis from 18 countries in the WHO African Region, 6 in the Eastern Mediterranean Region, 3 in the South-East Asia Region, 3 in the Western Pacific Region and 2 in the Region of the Americas. In 23 countries suspected of having endemic trachoma no reliable district-level population-based data were available. In China and India, data were limited to a few districts. The data highlighted important regional differences and marked national variations in prevalence of active trachoma and trichiasis. CONCLUSION: This is the first attempt to summarize and map the existing population-based data on active trachoma and trichiasis. The lack of data in many countries remains an important obstacle to trachoma control efforts.

Adolescent↗
PubMed2006

Gender disadvantage and reproductive health risk factors for common mental disorders in women: a community survey in India.

BACKGROUND: Gender disadvantage and reproductive health are major determinants of women's health in developing countries. OBJECTIVE: To determine the association of factors indicative of gender disadvantage and reproductive health with the risk of common mental disorders (CMDs) in women. DESIGN: Cross-sectional survey from November 1, 2001, to June 15, 2003. PARTICIPANTS: A total of 3000 women randomly selected from a sampling frame of women aged 18 to 45 years in Goa; 2494 women participated. MAIN OUTCOME MEASURES: The primary outcome was the presence of a CMD, as defined by the Revised Clinical Interview Schedule. An interview and blood and vaginal/urine specimens were collected to ascertain risk factors. RESULTS: The prevalence of CMD was 6.6% (95% confidence interval [CI], 5.7%-7.6%). Mixed anxiety-depressive disorder was the most common diagnosis (64.8%). Factors independently associated with the risk for CMD were factors indicative of gender disadvantage, particularly sexual violence by the husband (odds ratio [OR], 2.3; 95% CI, 1.1-4.6), being widowed or separated (OR, 5.4; 95% CI, 1.0-30.0), having low autonomy in decision making (OR, 1.98; 95% CI, 1.2-3.2), and having low levels of support from one's family (OR, 2.2; 95% CI, 1.4-3.3); reproductive health factors, particularly gynecological complaints such as vaginal discharge (OR, 3.2; 95% CI, 2.2-4.8) and dyspareunia (OR, 2.5; 95% CI, 1.4-4.6); and factors indicative of severe economic difficulties, such as hunger (OR, 2.7; 95% CI, 1.6-4.6). There was no association between biological indicators (anemia and reproductive tract infections) and CMD. CONCLUSIONS: The clinical assessment of CMD in women must include exploration of violence and gender disadvantage. Gynecological symptoms may be somatic equivalents of CMD in women in Asian cultures.

Adolescent↗
PubMed2006

The SAFE strategy for trachoma control: Using operational research for policy, planning and implementation.

Trachoma is a neglected disease and also the world's leading infectious cause of blindness. It causes misery, dependency and is a barrier to development. Trachoma is controlled by a WHO-endorsed integrated strategy of surgery for trichiasis, antibiotic therapy, facial cleanliness and environmental improvement, which is known by the acronym SAFE. The strategy is based on evidence from field trials and is continually being refined by operational research that informs national policy and planning; the strategy has affected both programme delivery and implementation. As a result of the findings of operational research, surgery is now frequently conducted by paramedics in communities rather than by ophthalmologists in hospitals; yearly mass distribution of a single oral dose of azithromycin has replaced the use of topical tetracycline; and the promotion of better hygiene, face-washing and the use of latrines are used to reduce transmission. Those who implement programmes have been equal partners in conducting operational research thus reducing the "know-do" gap and minimizing the lag that often exists between the completion of trials and putting their results into practice. Operational research has become a part of practice. Although there are still many questions without answers, national programme coordinators have a reasonable expectation that trachoma control programmes based on SAFE will work.

Anti-Bacterial Agents↗
PubMed2005

Risk factors influencing HIV infection incidence in a rural African population: a nested case-control study.

BACKGROUND: Risk factors influencing the incidence of human immunodeficiency virus (HIV) infection were investigated in a case-control study nested within a community-randomized trial of treatment of syndromic sexually transmitted infections (STIs) in rural Tanzania. METHODS: Case patients were persons who became HIV positive, and control subjects were randomly selected from among persons who remained HIV negative. For each sex, we obtained adjusted odds ratios (ORs) and population-attributable fractions (PAFs) for biomedical and behavioral factors. RESULTS: We analyzed 92 case patients and 903 control subjects. In both sexes, the incidence of HIV infection was significantly higher in subjects with an HIV-positive spouse than in those with HIV-negative spouse (men: OR, 25.1; women: OR, 34.0). The incidence of HIV infection was significantly higher in those who became positive for herpes simplex virus type 2 (HSV-2) (men: OR, 5.60; women: OR, 4.76) and those who were HSV-2-positive at baseline (men: OR, 3.66; women: OR, 2.88) than in subjects who were HSV-2 negative. In women, living elsewhere (OR, 3.22) and never having given birth (OR, 4.27) were significant risk factors. After adjustment, the incidence of HIV infection was not significantly associated with a history of injections or STIs in either sex. CONCLUSION: HSV-2 infection was the most important risk factor for HIV infection, which highlights the need for HSV-2 interventions in HIV infection control, and there were particularly strong associations with recent HSV-2 seroconversion. The PAF associated with having an HIV-positive spouse was low, but this is likely to increase during the epidemic.

Adolescent↗
PubMed2005

Is sexual contact with sex workers important in driving the HIV epidemic among men in rural Zimbabwe?

OBJECTIVE: To establish the importance of commercial sex in driving the HIV epidemic in the general population by determining risk factors for HIV infection among male mine and farm workers and estimating the fraction of prevalent HIV infections attributable to sexual contact with sex workers (SWs). SETTING: Five commercial farms and 2 mines in Mashonaland West, Zimbabwe. METHODS: A cross-sectional interviewer-administered questionnaire and urine survey of 1405 male workers. Urine samples were tested for HIV antibodies by a particle agglutination test and enzyme-linked immunosorbent assay and for Chlamydia trachomatis and Neisseria gonorrhoeae using a polymerase chain reaction assay. RESULTS: The overall prevalence of HIV antibodies was 27.3% (95% confidence interval [CI]: 24.8 to 29.5), that of C. trachomatis was 1.5% (95% CI: 1.0 to 2.1), and that of N. gonorrhoeae was 0.5% (95% CI: 0.1 to 0.9). A total of 48.4% (95% CI: 45.8 to 51.0) of men reported ever having had sexual contact with an SW, and 29.3% (95% CI: 26.9 to 31.7) reported contact in the past year. HIV was more common among men who reported SW contact on univariate (1.9% [95% CI: 1.5 to 2.4]) and multivariate (1.4% [95% CI: 1.0 to 1.8]) analysis after adjusting for confounding. HIV was also strongly associated with self-reported genital ulceration in the previous 6 months (adjusted odds ratio [OR] = 3.1, 95% CI: 2.2 to 4.3). Genital ulceration and SW contact were highly correlated. A total of 19.6% of HIV infections in men could be attributed to ever having had sexual contact with an SW (95% CI: 10.8 to 27.6). CONCLUSIONS: An appreciable proportion of HIV infection in men is attributable to sexual contact with SWs. Consideration should be given to developing interventions that target male clients of SWs.

Adult↗
PubMed2005

Single-dose azithromycin versus penicillin G benzathine for the treatment of early syphilis.

BACKGROUND: Pilot studies suggest that a single, 2-g oral dose of azithromycin may be an alternative to a 2.4-MU intramuscular dose of penicillin G benzathine in the prevention and treatment of syphilis. We evaluated the efficacy of treatment with azithromycin in a developing country. METHODS: A total of 328 subjects, 25 with primary and 303 with high-titer (a titer of at least 1:8 on a rapid plasmin reagin [RPR] test) latent syphilis, were recruited through screening of high-risk populations in Mbeya, Tanzania, and randomly assigned to receive 2 g of azithromycin orally (163 subjects) or 2.4 million units of penicillin G benzathine intramuscularly (165 subjects). The primary outcome was treatment efficacy, with cure defined serologically (a decline in the RPR titer of at least two dilutions by nine months after treatment) and, in primary syphilis, by epithelialization of ulcers within one or two weeks. RESULTS: The average age of participants was 27.0 years, 235 (71.6 percent) were female, and 171 (52.1 percent) were seropositive for human immunodeficiency virus. Cure rates were 97.7 percent (95 percent confidence interval, 94.0 to 99.4) in the azithromycin group and 95.0 percent (95 percent confidence interval, 90.6 to 97.8) in the penicillin G benzathine group (95 percent confidence interval for the difference, -1.7 to 7.1 percent), achieving prespecified criteria for equivalence. Cure rates were also similar three and six months after treatment in the two groups and in all subgroups. Cure rates at three months were 59.4 percent (95 percent confidence interval, 51.8 to 67.1) in the azithromycin group and 59.5 percent (95 percent confidence interval, 51.8 to 67.3) in the penicillin G benzathine group and at six months were 85.5 percent (95 percent confidence interval, 79.4 to 90.6) and 81.5 percent (95 percent confidence interval, 74.8 to 87.4), respectively. CONCLUSIONS: Single-dose oral azithromycin is effective in treating syphilis and may be particularly useful in developing countries in which the use of penicillin G benzathine injections is problematic. However, recent reports of azithromycin-resistant Treponema pallidum in the United States indicate the importance of continued monitoring for resistance.

Administration, Oral↗
PubMed2005

Chronic fatigue in developing countries: population based survey of women in India.

OBJECTIVES: To describe the prevalence of and risk factors for chronic fatigue in a developing country; in particular, to determine the association of anaemia, mental health, and gender disadvantage factors with chronic fatigue. DESIGN: Community survey. SETTING: Primary health centre catchment area in Goa, India. PARTICIPANTS: 3000 randomly sampled women aged 18 to 50 years. MAIN OUTCOME MEASURES: Data on the primary outcome (reporting of fatigue for at least six months) and psychosocial exposures elicited by structured interview; presence of anaemia determined from a blood sample. RESULTS: 2494 (83%) women consented to participate; 12.1% (95% confidence interval 10.8 to 13.4%) complained of chronic fatigue. In multivariate analyses, older women (P = 0.03) and those experiencing socioeconomic deprivation-less education (P < 0.001), families in debt (P = 0.09), or hunger in the past three months (P = 0.03)-were more likely to report chronic fatigue. After adjustment for these factors, factors indicating gender disadvantage (notably sexual violence by the husband; P < 0.001) and poor mental health (P < 0.001) were strongly associated with chronic fatigue. Although women with a high body mass index had a reduced risk, suggesting an influence of poor nutrition, no association was found between chronic fatigue and haemoglobin concentrations. CONCLUSIONS: Chronic fatigue was commonly reported by women in this community study from India. The strongest associations with chronic fatigue were for psychosocial factors indicative of poor mental health and gender disadvantage.

Adolescent↗
PubMed2005

Why do women complain of vaginal discharge? A population survey of infectious and pyschosocial risk factors in a South Asian community.

BACKGROUND: Vaginal discharge is a common complaint, particularly among women in Asia. Although presumed to be caused by reproductive tract infections (RTIs), the association between the complaint and the presence of RTIs is weak. This study aimed to investigate the risk factors of the complaint of vaginal discharge. METHODS: We conducted a community-based survey of 3000 women aged 18-50 years, randomly sampled from a population in Goa, India. Women who gave informed consent were invited to participate in a structured interview, which elicited data on the primary outcome (the experience of current abnormal vaginal discharge) and psychosocial exposures: gender adversity; symptoms of somatoform disorders; and common mental disorders (CMD). All women were required to provide vaginal and/or urine samples for diagnosis of RTIs using gold standard laboratory tests. Risk factors were analysed using logistic regression with the binary outcome of the complaint of vaginal discharge. RESULTS: Of the 2494 women (83%) who agreed to participate, 14.5% complained of having an abnormal vaginal discharge. Stress was the most common causal attribution for the complaint. The final multivariate model found that high scores for CMD (OR 2.16, 1.4-3.2) and somatoform disorders (6.23, 4.0-9.7) and the use of an intrauterine contraceptive device (1.86, 1.0-3.4) were independently associated with the complaint. Low literacy (0.54, 0.4-0.8) and age >40 years (0.29, 0.2-0.4) were associated with a reduced risk. RTI were not associated with the complaint (1.24, 0.9-1.6). CONCLUSIONS: Psychosocial factors have the strongest association with the complaint of vaginal discharge. Syndromic management algorithms need refinement so that women with complaints that are non-infectious in aetiology are offered psychosocial interventions.

Adolescent↗
PubMed2005

The appropriateness of core group interventions using presumptive periodic treatment among rural Zimbabwean women who exchange sex for gifts or money.

To map the characteristics of rural based sex workers in Zimbabwe with regard to demographics, mobility, behavior, HIV and sexually transmitted infection (STI) prevalence, to explore the appropriateness and feasibility of presumptive periodic treatment (PPT) for bacterial STIs as an HIV prevention intervention among these women, and to compare tolerability of 2 PPT regimens (1 g of azithromycin and 2 g of metronidazole+/-500 mg of ciprofloxacin). Five commercial farms and 2 mines in Mashonaland West, Zimbabwe. Three hundred sixty-three sex workers were recruited and completed a structured interviewer-administered questionnaire. Each participant had blood tested for antibody to HIV, herpes simplex virus 2 (HSV-2), and syphilis; urine tested for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG); and a vaginal swab tested for Trichomonas vaginalis (TV). Women were randomly assigned to receive a single dose of 1 of 2 PPT regimens and then followed to assess rates of side effects and reinfection. The overall prevalence of antibody to HIV was 55.7% (95% confidence interval [CI]: 50.6-60.9) and that of HSV-2 was 80.8% (95% CI: 76.7-84.9). The prevalence of CT and NG was low (CT=1.7%, 95% CI: 0.3-3.0); (NG=1.9%, 95% CI: 0.5-3.4), with a much higher prevalence of TV (TV=19.3%, 95% CI: 15.2-23.4). Prevalence of CT, NG, and TV was appreciably reduced 1 month after PPT but rose to pretreatment levels at the 2- and 3-month visits. The rate of moderate or severe side effects after PPT was low, but it was higher in the women who received ciprofloxacin in addition to azithromycin and metronidazole (P=0.007). It was feasible to access women who reported exchanging money or gifts for sex in rural communities, although many of these women engaged in sex work only infrequently. The prevalence of bacterial STIs was low, suggesting that PPT may not be an appropriate intervention in this setting. Rapid reinfection after PPT suggests that this needs to be given at monthly intervals to reduce prevalence of STIs.

Adult↗
PubMed2005

Participatory evaluations of trachoma control programmes in eight countries.

OBJECTIVES: Trachoma is a major cause of blindness. The objective of this initiative was to conduct participatory process evaluations of the trachoma control programmes receiving support from the International Trachoma Initiative in eight countries. METHODS: During each 2- to 4-week evaluation we analysed information collected at the central, district and community level through interviews, focus groups, questionnaires, direct observation of trachoma control activities, and existing data. RESULTS: Mapping and assessment of disease prevalence had been completed in four of eight countries. Integration of trachoma control activities into national planning and district-level service provision varied. Intersectoral partnerships to implement the SAFE strategy (i.e. surgery, antibiotics, facial cleanliness and environmental change) were well established in a few countries. In all eight countries, the number of surgeries performed annually was insufficient; and quality of surgery was rarely monitored. Mass distribution of antibiotics was carried out well in extremely resource-poor settings and good coverage was achieved, although the strategy for antibiotic distribution varied. Inadequate water and sanitation remained a major problem in all programme areas. Monitoring of programme activities was generally inadequate. The Morocco programme is an example from which lessons and processes can be learnt and adapted to other programme countries. CONCLUSIONS: Significant achievements have been made in implementing the SAFE strategy. Scaling up of activities to true national coverage should be planned and implemented provided the resources can be made available. Further standardization of how to assess, implement and monitor trachoma control activities will facilitate expansion of the programme.

Africa↗
PubMed2005

Antenatal syphilis screening in sub-Saharan Africa: lessons learned from Tanzania.

UNLABELLED: OBJECTIVES; To synthesise data from four recent studies in Tanzania examining maternal syphilis screening and its operational implementation in routine antenatal clinics (ANC), drawing lessons for strengthened antenatal services for the prevention of mother-to-child transmission (PMTCT) of HIV. METHODS: The impact of untreated maternal syphilis was examined in a retrospective cohort of 380 Tanzanian women. Effectiveness and cost-effectiveness of screening and single dose benzathine penicillin treatment were prospectively examined in 1688 pregnant women. Observation, interviews and facility audits were carried out in health facilities within nine districts to determine the operational reality of syphilis screening. RESULTS: Overall, 49% of women with untreated high titre syphilis experienced an adverse pregnancy outcome compared with 11% of uninfected women. Stillbirth and low birthweight rates among those treated for high- or low-titre syphilis were reduced to rates similar to those for uninfected women. The economic cost was $1.44 per woman screened and $10.56 per disability-adjusted life year saved. In the operational study, only 43% of 2256 ANC attenders observed were screened and only 61% of seroreactive women and 37% of their partners were treated. Adequate training, continuity of supplies, supervision and quality control are critical elements for strengthened antenatal services, but are frequently overlooked. CONCLUSIONS: Maternal syphilis has a severe impact on pregnancy outcome. Same-day screening and treatment strategies are clinically effective and highly cost-effective, but there are significant challenges to implementing syphilis screening programmes in sub-Saharan Africa. Current PMTCT interventions present an opportunity to reinforce and improve syphilis screening. Increasing PMTCT coverage will involve similar operational challenges to those faced by syphilis screening programmes.

Anti-Bacterial Agents↗
PubMed2005

In vitro effects of spectinomycin and ceftriaxone alone or in combination with other antibiotics against Chlamydia trachomatis.

The in vitro effects of spectinomycin and ceftriaxone, alone or in combination with erythromycin, ofloxacin, and doxycycline, against Chlamydia trachomatis were investigated by the checkerboard method and compared by Ridit (reference identical unit) analysis. A combination of spectinomycin with erythromycin or doxycycline was found to be more effective than that of ceftriaxone.

Anti-Bacterial Agents↗
PubMed2005

Mass treatment and the effect on the load of Chlamydia trachomatis infection in a trachoma-hyperendemic community.

PURPOSE: Trachoma remains a leading cause of blindness. Determining the most effective antibiotic treatment strategy is essential for the success of country-based trachoma control programs. METHODS: Baseline and 2-month follow-up examinations were performed in a trachoma-hyperendemic village. All residents were offered azithromycin for trachoma after baseline was determined. Infection with Chlamydia trachomatis and chlamydial load were determined by PCR. Clinical trachoma status was evaluated. A high chlamydial load was defined as a higher than median chlamydial load among those with infection. Risk factors were examined in multiple logistic regression models. Associations are presented as odds ratios and 95% confidence intervals. RESULTS: At baseline, 57% of participants were infected with C. trachomatis. Although clinical trachoma correlated with infection, 23% of participants with high chlamydial loads showed no clinical signs. Adults represented only 10% of the population with high loads. Treatment significantly decreased the proportion positive in the community and the load in the community. However, 27% of individuals with high loads at baseline who received treatment also were infected at 2 months. Of those, 93% with high loads at 2 months were aged < or =10 years. CONCLUSIONS: Although most of the chlamydial load in this community resided in children, 10% of the high load resided in adults, most of whom did not have follicular trachoma and in whom the infection would be missed under treatment strategies that focus on clinical disease or children. These data support a mass treatment strategy for hyperendemic communities, at least as a first approach. In addition, treatment of children age < or =2 years should be reexamined, as >30% with high loads at baseline remained infected at 2 months, despite monitored treatment according to weight.

Adolescent↗
PubMed2005

Risk factors for postsurgical trichiasis recurrence in a trachoma-endemic area.

PURPOSE: The World Health Organization recommends trichiasis surgery to prevent blindness caused by trachoma; however, recurrence is common. Risk factors for recurrence have not been widely studied, particularly in trachoma hyperendemic areas. METHODS: Three hundred ninety-four persons with trichiasis in Tanzania were examined. Participants had undergone surgery >18 months before the study. Trichiasis recurrence and active trachoma at study visit were assessed. Ocular swabs were collected and tested for Chlamydia trachomatis. Household members were examined for active trachoma. RESULTS: Of the surgical eyes, 28% had recurrence; 40% of patients had recurrence in one or both eyes. Rates did not vary by time since surgery. Eye-level recurrence rates varied significantly across districts, ranging from 16% to 38%. Current chlamydial infection among surgical cases was low (6%) and was not associated with recurrence. Recurrence was associated with tarsal conjunctival inflammation (OR: 2.4; 95% confidence interval [CI]: 1.6-3.8) and residence in the Kongwa district (OR: 2.3; 95% CI: 1.2-4.6). CONCLUSIONS: Recurrence after trichiasis surgery is high, suggesting that vigilant follow-up in surgical cases is needed to reduce blindness. Recurrence is associated with evidence of inflammation in the tarsal conjunctiva, although it is not clear whether the inflammation contributes to recurrence, or is a result of the recurrence. Longitudinal studies of trichiasis patients after surgery are needed.

Aged↗
PubMed2005

Detection of gonococcal infection : pros and cons of a rapid test.

WHO estimates that 62 million cases of gonorrhea occur annually worldwide. Untreated infection can cause serious long-term complications, especially in women. In addition, Neisseria gonorrheae infection can facilitate HIV transmission, and babies born to infected mothers are at risk of ocular infection, which can lead to blindness. Where diagnostic facilities are lacking, gonorrhea can be treated syndromically. However, this inevitably leads to over-treatment, especially in women in whom the syndrome of vaginal discharge may be due not to N. gonorrheae infection but to several other more prevalent conditions. Over-treatment is a major concern because of widespread N. gonorrheae antibiotic resistance. Moreover, a high proportion of gonorrhea cases are asymptomatic and so do not present for syndromic management. Such cases will only be detected by screening tests. The gold standard test for the detection of N. gonorrheae is culture, which has high sensitivity and specificity. However, it requires well trained staff and its performance is affected by specimen transport conditions. Other options include microscopy and tests that detect gonococcal antigen or nucleic acid. Nucleic acid amplification tests (NAATs) have higher sensitivity and can be used on non-invasive samples (urine). However, they can cross-react with other Neisseria species and are expensive, requiring highly trained staff and sophisticated equipment. In settings where patients are asked to return for laboratory results, some infected patients never receive treatment as they fail to return for their test results. This reduction in treatment, and the possible onward transmission of N. gonorrheae during any delay in treatment, means that a rapid test of lower sensitivity may be more effective if it results in patients being treated at the initial visit. Indeed, even with the low sensitivity of currently available rapid tests (50-70%), modeling shows that they can outperform gold standard tests in populations with high sexual activity and/or low return rates. Unfortunately, however, most of the rapid tests currently available are immunoassays that are quite expensive and involve many steps, which limit their current usefulness. In summary, the pros and cons of using a rapid test are dependent on the setting. Culture or NAATs remain the best choice in an ideal setting. However, in settings where laboratory facilities are not available, or in high-risk populations where return rates are low, rapid tests may be the most effective way of diagnosing gonorrhea. Their optimal use in these settings requires the development of simpler and cheaper rapid tests.

Bacteriological Techniques↗