p24 antigen detection on dried blood spots is a feasible and reliable test for infant HIV infection in rural Tanzania

The difficulty of diagnosing HIV in infants is a major obstacle to early antiretroviral therapy (ART) in resource-limited settings. As serological tests are unreliable during the first 18 months of life, and the cost and complexity of polymerase chain reaction (PCR)-based assays limit their access in resource-limited settings, p24 antigen detection has emerged as an alternative diagnostic tool. In this study, the performance of an ultrasensitive p24 antigen assay on dried blood spots was evaluated under field conditions in rural Tanzania. Specimens were stored and shipped at tropical room temperature, and analysed within six weeks. In total, 27 consecutive children aged <18 months and exposed to vertical HIV transmission were enrolled. Overall sensitivity and specificity was 100% (95% confidence interval [CI], 47.8-100) and 95.5% (95% CI, 77.2-99.9), respectively. Our findings suggest that detection of p24 antigen on dried blood spots can be a reliable and feasible diagnostic tool for infant HIV infection in rural resource-limited settings.

The effects of genital schistosoma haematobium on human papillomavirus and the development of cervical neoplasia after five years in a Zimbabwean population

BACKGROUND

High-risk human papillomavirus (HPV) is responsible for cervical cancer and genital Schistosoma haematobium infection has been hypothesized to be an additional co-factor or even an independent risk factor for cervical neoplasia. The present study aimed to investigate the impact of schistosomiasis on HPV persistence and development of cell atypia in a group of rural Zimbabwean women with confirmed high-risk HPV.

METHODS

A five-year follow-up was done among women previously included in a study on genital schistosomiasis. Women who had high-risk HPV at baseline were invited after 5 years for examination of cell atypia, genital schistosomiasis, and high-risk HPV. Both vaginal lavage samples (low-cost) and cervix brush samples (high-cost) were obtained for further analysis.

RESULTS

Thirty-seven women were re-examined. Genital Schistosoma haematobium of a minimum of five years' duration was associated with the development high-grade squamous intraepithelial neoplasia, but not with persistent high-risk HPV. There was a high concordance between the brush and vaginal lavage (96.3% agreement, kappa 0.93); however, the number of beta-globin negative vaginal lavage samples was unacceptably high.

CONCLUSIONS

Findings warrant an exploration in a larger longitudinal study where a vaginal swab should be explored.

Prevalence of urinary schistosomiasis and HIV in females living in a rural community of Zimbabwe: does age matter?

A cross-sectional study was conducted on 544 women living in Mupfure rural area of Zimbabwe to determine whether infection with urinary schistosomiasis is associated with HIV infection. Schistosoma haematobium infection was examined in urine samples and HIV infection was determined in sera. The prevalence of S. haematobium infection was highest (60%) in women below 20 years of age and declined to 29% in the oldest age group (test for trends, P<0.001). Overall, women infected with urinary schistosomiasis had an HIV prevalence of 33.3%, whilst women without urinary schistosomiasis had an HIV prevalence of 25.6% (chi(2), P=0.053). Women above the age of 35 years and infected with urinary schistosomiasis had a significantly higher HIV prevalence (37.5%) than those without urinary schistosomiasis (16.8%; chi(2), P<0.001).

Control of Biomphalaria pfeifferi population and schistosomiasis transmission in Ethiopia using the soap berry endod (Phytolacca dodecandra), with special emphasis on application methods

The endod (Phytolacca dodecandra)-based schistosomiasis mansoni control project was implemented in Ethiopia between 1994 and 1999. The aim was to develop an effective, cheap and sustainable method of controlling schistosomiasis. First, different formulations of the Ethiopian endod strain 44 (E-44) were compared for potency in the laboratory. Secondly, spray and drip-feeding methods were compared for simplicity and effectiveness in the field. Lastly, the efficacy of endod powder soap was compared with the endod spray method. In Bati stream, endod powder soap was distributed to the residents every weekend at laundry sites. In Worke stream, endod was sprayed along a 1-km stretch of the stream at 3-month intervals. No endod was applied in Harbu stream. The immediate and long-term effects of endod application on the snail population and schistosomal infection were determined. Using the spray method, 100% snail mortality could be obtained, and it was simpler and more effective than the drip-feeding method. Snail mortality ranged from 20 to 100% using endod soap. There was a progressive decline in the snail population and infection in Bati stream compared with Worke stream, mainly due to sustained use of endod soap. The advantages and disadvantages of the different endod delivery systems are discussed.

Assessment of eosinophil cationic protein as a possible diagnostic marker for female genital schistosomiasis in women living in a Schistosoma haematobium endemic area

Eosinophil cationic protein (ECP) levels were measured in vaginal lavage extracts from 518 Zimbabwean reproductive women, age range 15-49 years, to assess the potential use of ECP as a diagnostic marker for female genital schistosomiasis (FGS). One hundred and fifty women had confirmed FGS status. These included 77 (cases) women who had ova in genital tissue and 73 (controls) women who had no ova in genital tissue. Participants were examined at baseline, 3 and 15 months post-treatment with praziquantel. ECP levels were determined using the enzyme linked immunosorbent assay (ECP-ELISA). ECP levels from 18 Norwegian women were used to calculate the diagnostic values of the test. FGS was diagnosed from the study population using genital biopsy and smears. Women were also diagnosed for urinary schistosomiasis using the urine filtration technique. The prevalence of urinary schistosomiasis was 39 % at baseline and this declined to 8% and 6% at 3 and 15 month post-treatment surveys, respectively. There was a higher mean ECP level in women with FGS, 889.3 ng/mL (95% CI: 457.0-1327.5) compared to the endemic control group, 359.1 ng/mL (95%, CI: 227.3-490.9), P = 0.027. Mean ECP levels declined at 3 months following treatment of infected individuals. There was no correlation between ECP levels and tissue ova density, and urine egg intensity. The sensitivity, specificity, positive and negative predictive values for the ECP-ELISA test were 35%, 80%, 65% and 53%, respectively. Our results indicate that FGS causes an inflammatory immune response that increases ECP levels in genital fluid. Treatment of schistosomiasis results in a regression of pathology and a decline in ECP levels. However, other factors such as allergy and microbial infection could also be responsible for increased ECP levels in genital mucosa. These conditions will affect the validity of the test in diagnosis of FGS.

The relationships between dehydroepiandrosterone sulphate (DHEAS), the intensity of Schistosoma mansoni infection and parasite-specific antibody responses. A cross-sectional study in residents of endemic communities in north-east Ethiopia

There are speculations that the puberty-related hormone dehydroepiandrosterone sulphate (DHEAS) might influence the intensity of infection and immune responses during Schistosoma infections. We studied the relationships between DHEAS, intensity of Schistosoma mansoni infection and humoral immune responses in 135 residents of Ethiopia. Serum levels of eight antibody isotypes against worm and egg antigens were determined by ELISA. DHEAS was measured with an immunoluminometric assay. There was a significant negative correlation between serum levels of DHEAS and intensity of S. mansoni infection. A significant increase in serum levels of DHEAS in the age group 15-19 years was accompanied by a progressive decline in the intensity of infection. Peak level of DHEAS coincided with the lowest intensity of infection in the age group 20-29 years. Multiple regression analysis showed that DHEAS alone had a significant (p<0.0001) negative effect when the effect of age was removed. Age also had a significant (p<0.0001) negative effect on the intensity of infection, after removing the effect of DHEAS. The two predictive variables accounted for 34.4% of the decline in the intensity of infection. Age accounted for 24.9%, whereas DHEAS accounted for 15.2% when the effect of each of the variables was removed. DHEAS had significant negative effects on AWA-specific IgG (p=0.02) and IgG1 (p=0.018) and SEA-specific IgG1 (p=0.009), after adjusting for the effect of age.

Differences in prevalence, intensity of infection and parasite-specific antibody levels do not predict different age-infection profiles

Acquired immunity is believed to influence the age-infection profile of Schistosoma infections. We compared antibody responses against Schistosoma mansoni adult worm antigen (AWA) and soluble egg antigen (SEA) in 164 residents of two communities with different levels of infection. IgG, IgA, IgM, IgE, and IgG subclass 1 to 4 antibodies were determined by ELISA. Seventy-five of the subjects were from Harbu, an area with a prevalence of 39% and an intensity of infection of 116 eggs per gram of stool (EPG), whereas 89 subjects were from Bati, with a prevalence of 66% and intensity of infection of 256 EPG. In both communities the prevalence and the intensity of infection were highest in the age group 10-14 years, although both were significantly higher in Bati than in Harbu. Mean levels of AWA-specific IgA, IgM, IgG, IgG1 and IgG2, and of SEA-specific IgG, IgM, IgG2 and IgG3 were significantly higher in Bati than in Harbu. However, mean levels of IgE against worm and egg antigens were significantly higher in Harbu than in Bati. Significant differences were detected in the levels of IgA, IgE, IgG, IgM, IgG1 and IgG2 against AWA, and in IgE, IgM, IgG2 and IgG3 against SEA according to the place of residence. The levels of anti-AWA IgG, IgG1 and IgG2 and anti-SEA IgG, IgG1 and IgG4 were significantly associated with the intensity of infection. Anti-AWA IgM levels were associated with age, whereas sex and age had interacting effects on the levels of AWA-specific IgG1 and SEA-specific IgG and IgM. Antibody responses exhibited different age-related patterns in the two communities. This may indicate that differences in history of exposure influence the evolution of immune responses. However, the study did not support the view that differences in antibody levels between communities subject to different levels of infection result in a systematic deviation in age-infection profile (the "peak shift").

Control of Schistosoma mansoni by the soapberry Endod (Phytolacca dodecandra) in Wollo, northeastern Ethiopia: post-intervention prevalence

OBJECTIVES

To record the effect of Endod soap and spraying of soaked Endod suspension on the prevalence of human schistosomiasis.

DESIGN

A cross-sectional epidemiological study in which pre- and post-intervention parasitological results were compared.

SETTING

Kemise, Bati and Harbu towns in northeastern Ethiopia.

SUBJECTS

The study subjects included all members of the five per cent households systematically selected from the three towns.

RESULTS

In Kemise town, where suspension of ground Endod was sprayed on the stream containing infected snails, the prevalence of the disease was reduced from 59% to 53% and the mean intensity of infection was reduced from 239 eggs per gram (EPG) of faeces to 99 EPG (p < 0.05). In Bati town where Endod soap approach was used, the respective reduction in the prevalence and intensity of infection was from 51% to 43% and from 195 EPG to 162 EPG (p < 0.05). There was also a significant reduction of the disease in the control town probably due to the effects of praziquantel treatment and other factors.

CONCLUSION

The reduction achieved in the prevalence and intensity of schistosomiasis after an intervention period of four years was limited. This observation corroborates the fact that molluscicides must always be considered as supplementary to chemotherapy in the control of schistosomiasis. Although both approaches can be used, the spraying approach appears to be simpler and more feasible because two or three times yearly application of Endod suspension would suppress snail population and reduce transmission. Nevertheless, the choice as to what approach to use must be made on the basis of community preference, and for some soap-effect of Endod would be attractive

Epidemiological studies on intestinal schistosomiasis in Wondo Genet, southern Ethiopia

A cross-sectional epidemiological survey was made on intestinal schistosomiasis due to Schistosoma mansoni in Wondo Genet, southern Ethiopia, in 1999 to generate preintervention parasitological and malacological baseline data to be used as a reference in evaluation of community-based pilot control trial to be launched using wild-growing Endod. A total of 3000 stool specimens were collected from schoolchildren enrolled in 14 schools and microscopically examined using Kato method. The overall prevalence and intensity of schistosomiasis mansoni was 34.6% and 184 eggs per gram of stool (EPG), respectively. Children excreting Schistosoma mansoni eggs were found in all of the 14 schools surveyed with a prevalence of infection ranging from 1.9% in Abaye School to 80.6% in Shesha Kekele School. The overall prevalence of S. mansoni infection among males and females was 38.4% and 27.3%, respectively (P = 0.0001, 95% C.I = 7.5%-14.7%) where as the intensity of infection was 186 EPG and 181 EPG, respectively (P = 0.8045, 95% C.I = 1.17%-1.23%). Malacological surveys of 27 water contact sites revealed the occurrence of Biomphalaria pfeifferi in 8 sites out of which 3 harbored infected snails shedding schistosome cercariae. The necessity for initiating community-based sustainable control programme is discussed.

Age- and sex-related differences in antibody responses against Schistosoma mansoni soluble egg antigen in a cohort of school children in Ethiopia

Acquired immunity is believed to be the main factor in the age-related differences in prevalence and intensity of Schistosoma infections. We studied antibody responses against S. mansoni soluble egg antigen (SEA) by ELISA in children before treatment, 5 weeks and one year after treatment. After screening for S. mansoni infection, positive children were treated with praziquantel (40 mg per kg body weight). Infection rate was significantly higher in boys younger than 12 years than in girls in the same age group. Levels of all antibody isotypes, except IgG1 (before treatment) or IgA (one year after treatment), were higher in children older or equal to 12 years than in those younger. The difference between age groups was significant for IgE, IgM, IgG3 and IgG4 (before treatment) and IgE (one year after treatment). Similarly, all antibody isotypes, except IgE, before treatment were higher in boys than in girls. At 5 weeks after treatment, IgG, IgE and IgG1 showed an increasing tendency, whereas IgM and IgG3 tended to decrease. One year after treatment, significant decreases were observed in IgG, IgG1 and IgG4 and a significant increase in IgG2 levels. The study presents further evidence for the difference in acquired immunity between younger and older children, and between boys and girls. The study also suggests that praziquantel differentially affects antibody responses against S. mansoni SEA.

Implication of Papio anubis in the transmission of intestinal schistosomiasis in three new foci in Kime area, Ethiopia

Epidemiological studies were conducted in the Lake Langano area in the Rift Valley of Ethiopia to determine the occurrence of schistosomiasis and assess factors involved in its transmission. Microscopic examination of faecal specimens from free ranging Papio anubis (anubis baboon) troops from Bishan Gari and Burka Dita forest reserves revealed Schistosoma mansoni eggs with a prevalence of 12.1% (11/91) and 26.2%(34/130), respectively. The eggs were viable as confirmed by miracidial hatching and infectivity tests. Out of the total 12 communities (three schools, five villages and one herdsmen community) surveyed for schistosomiasis around Lake Langano, individuals excreting S. mansoni eggs were found in nine communities with prevalence of infection ranging from 1.4 to 43%. The intensity of infection ranged from 24 EPG (eggs per gram of faeces) to 243 EPG. Excretion of viable eggs by the baboons indicate that they play a role in maintenance of S. mansoni infection in the locality. The detection of S. mansoni eggs in young children, collection of cercarial-infected Biomphalaria pfeifferi in water bodies, and establishment of S. mansoni infection in lab-bred mice have confirmed establishment of transmission foci in Kime area, south-east of Lake Langano. However, the lake itself does not seem to support transmission of schistosomiasis since no snails were found along the shore of the Lake. Further investigations are indicated to fully elucidate the role baboons play in the epidemiology of schistosomiasis in the Rift Valley of Ethiopia. The risk of introduction of water-based development projects in these new endemic foci in relation to S. mansoni infection in the baboons is discussed.

Praziquantel side effects and efficacy related to Schistosoma mansoni egg loads and morbidity in primary school children in north-east Ethiopia

A total of 611 Schistosoma mansoni infected primary school children from three schools in north-east Ethiopia were treated with praziquantel at 40 mg/kg body weight in a single dose. Pre-treatment, 40.4% had no presenting symptoms and 30-40% had nausea, abdominal cramps and/or bloody-mucoid diarrhoea. None of the pre-treatment symptoms was related to nutritional status, intensity of S. mansoni egg excretion, or to the presence of other concomitant intestinal parasitic infections. During the first 4-6 h post-treatment observation period, 90 (14.7%) children self-presented with severe gastro-intestinal symptoms. Children who self-presented with severe symptoms had a higher mean age and mean S. mansoni egg excretion compared with children who did not self-present. The following day a total of 529 (86.6%) children, including all who self-presented during the first 4-6 h post-treatment, reported for clinical check-up and were subjected to a structured questionnaire interview on symptoms they had experienced over the time lapse following treatment. Among these, 91.5% reported one or more treatment related symptoms which were at times severe. Abdominal cramps (86.9%), diarrhoea with blood and/or mucus (49.5%), dizziness (31.2%) and vomiting (24.9%) were the most common treatment related symptoms. Skin rash with oedema were observed in four cases. Among treatment related symptoms, the combination of abdominal cramps with vomiting, bloody diarrhoea, vomiting alone and general weakness were significantly higher among the malnourished. A proportion of these symptoms increased with increasing categories of S. mansoni egg excretion before and after adjusting for nutritional status and concurrent intestinal parasitic infections. Overall, the cure rate of praziquantel, among 541 children who had stool examination 5 weeks after treatment was 83.2% and this rate decreased with increasing pre-treatment egg counts. In conclusion, most of the treatment related symptoms were mild. However, some of the objective symptoms were at times severe and may reduce drug compliance in primary health care based population chemotherapy.

Delayed reinfection of Schistosoma mansoni in the Blue Nile Valley of western Ethiopia 10 years after mass chemotherapy

In the Blue Nile Valley of western Ethiopia a successful control programme against Schistosomiasis mansoni starting from 1985 was in 1989 interrupted by local guerrilla warfare. The control was based on human mass chemotherapy campaigns during the rainy season of 1985 and 1986 and a limited annual, focal molluscicidal activity where re-infection was demonstrated. In 1995 the area was revisited and selected schools in previously hyperinfected villages were examined for reinfection. The results were compared to re-calculated figures for the 5-19 year age group from previous pre-, per- and post-control surveys in the same localities. In 1995 prevalence rates in the 5-19 year age group had risen to 68% (Salba-Korka) and 63% (Sirba), which are very close to the 1985-1986 pre-control prevalences. Infection intensities, however, had not risen to the same degree. In Salba-Korka the 1986 pre-control geometric mean S. mansoni eggs per gram of faeces in the 5-19 year age group was 73, after mass treatment until 1989 it was close to 0, whereas in 1995 it was still only 27. In Sirba the result was similar. This might indicate a slower transmission rate after the control period than previously. The reported seasonality of transmission and the local use of the molluscicidal bark of the 'Bitza' tree might possibly have had some delaying effect.

Epidemiology of schistosomiasis mansoni in three endemic communities in north-east Ethiopia: baseline characteristics before endod based intervention

As part of a pre-intervention baseline data collection the epidemiological characteristics of schistosomiasis mansoni were studied in 3 endemic communities (Kemise, Harbu and Bati towns) in northeast Ethiopia in April and May 1994. The objective was to generate data based on which post-intervention differences (in changes), if any, in transmission level could partly be explained for the 3 towns. After calculating the sample size required for each town 132, 75, 158 households were selected by systematic random sampling from Kemise, Harbu and Bati, respectively and all members of the selected households stool was examined by the Kato's thick smear method. Eighty eight and 85% of the houses harboured one or more cases of Schistosoma mansoni in Kemise and in Bati, respectively, all members of the households being positive in 27% in Kemise and in 28% in Bati. The overall prevalences were 59%, 33% and 51% in Kemise, Harbu and Bati, respectively, with the corresponding geometric mean egg counts (epg) of 240, 123 and 195 for positives and 26.5 and 15 for the whole populations. All ages combined, there were no significant differences due to sex both in prevalence and intensity of infection. By age, children in the 10-14 years age group were most affected (p = 0.007), their prevalences reaching 86%, 52% and 66% in Kemise, Harbu and Bati, respectively and their corresponding geometric mean epg being 377, 157 and 401, respectively. Heavy infection (> 100 epg) reached 42%, 32% and 16% in Kemise, Bati and Harbu, respectively, reaching an average of 55% among the 10-14 years of age. The implications of the epidemiological findings and the possible use of the household approach for rapid assessment of schistosomiasis magnitude in an area are discussed.

[Dengue fever. Another infectious disease out of control?]

In the 1950s dengue fever left its home in South-East Asia. The result, as we see it 40 years later, is terrifying. From being an almost unknown infection, dengue fever is today's most common arboviral disease with up to 100 million cases annually. In addition, the clinical picture has changed from a benign influenza-like disorder (classic dengue fever) to a serious disease with bleeding and hypovolemic shock (dengue hemorrhagic fever). In this article the authors give an overview of the present epidemiology, prognosis and possible preventive measures against dengue fever.

[Dengue fever imported to Norway. Serologically confirmed cases 1991-96]

With up to 100 million cases annually, dengue fever is today's most important arboviral disease. Dengue fever is endemic in many parts of South-East Asia, the Indian subcontinent, Oceania and the Americas. The disease mainly affects the local population, but occasionally also visitors from non-endemic areas. In this article we present epidemiological and clinical data on all 26 cases with serological confirmed dengue fever diagnosed in Norway in 1991-1996. 21 patients (81%) were infected in Asia. Typical exanthema, leucopenia, and thrombocytopenia were seen in 71%, 79% and 84% of the cases, respectively. A 37-year-old Indian-born woman developed dengue haemorrhagic fever grade 1 after a visit to New Delhi, while the remaining 25 patients had classical dengue fever. Postinfectious complications were common, and four weeks after the acute illness, hair loss, mental depression and asthenia were reported by 45%, 50% and 100% of the cases, respectively.

Schistosomiasis in women: manifestations in the upper reproductive tract

Female genital schistosomiasis (FGS) is a neglected disease entity which may give rise to considerable suffering among women of child-bearing age in areas where schistosomiasis (especially due to Schistosoma haematobium) is prevalent. The close relation between the vessels in genital organs and the urinary bladder enables the parasite to easily change location to virtually any organs in the female pelvic area. Symptoms concur with the anatomical location of worm pairs and their ova. Lesions of the lower female genital tract can easily be investigated by cytology, histology or direct demonstration of eggs in scrapings or biopsies whereas schistosomiasis of the upper genital tract is clinically indecipherable and less accessible for examination. In the literature there are references to FGS as a cause of infertility, complications of pregnancy, menstrual disorders, problems related to sexual intercourse, diagnostic similarities to STDs and cancer, unspecified complaints related to blood loss, chronic abdominal pain, social segregation and related psychological problems. The diagnosis of female upper genital schistosomiasis is difficult and the authors point out possible diagnostic procedures which might be helpful for further understanding of this complex entity.

Urine reagent strips for diagnosis of schistosomiasis haematobium in women of fertile age

Hematuria, proteinuria and leukocyturia were semiquantitatively assessed by reagent strips in single morning urine of women of fertile age visiting the outpatient department of the Mangochi district hospital, Malawi. This was part of a diagnostic approach to female genital schistosomiasis (FGS). In 51 women ova of Schistosoma haematobium were detected in urine by a filtration technique. In 33 of these women ova were also present in genital tissue as demonstrated by microscopic examination of biopsies. In 209 women no ova were found in the single urine filtered. There were significantly higher scores for hematuria, proteinuria and leukocyturia as well as of the combined reagent strip index (RSI) in egg-excreting than in egg-negative women. The sensitivity of a single hematuria, proteinuria and leukocyturia reading was 98, 84 and 73%, respectively. However, the respective specificity was only 24, 22 and 23%. The best prediction of urinary schistosomiasis was achieved by a +2 score for hematuria, of which the sensitivity was 94% and the specificity was 61%. The high false-positive rates can probably be explained by contamination of urine by vaginal secretion. Moreover, cases of schistosomiasis have probably been overlooked because only a single morning urine sample was examined. The total absence of hematuria, proteinuria and leukocyturia, however, may be used to rule out heavy infections in community surveys. There was no difference in reagent strip scores between women with genital and urinary schistosomiasis as compared with those with urinary tract lesions alone. Thus urine analysis reagent strip readings do not help to discriminate between S. haematobium infected women with and without FGS.

Reversibility of lower reproductive tract abnormalities in women with Schistosoma haematobium infection after treatment with praziquantel--an interim report

Little is known whether and to what extent antiparasitic treatment cures female genital schistosomiasis (FGS). Using a standard protocol, of twenty-one women with FGS nine were re-examined at two to nine weeks after they had been treated with praziquantel at a single dose of 40 mg/kg. Symptoms related to pathology of the urinary tract and to a lesser extent of genital pathology subsided in most patients. Schistosoma haematobium ova were no longer detectable in urine of any of the patients post-treatment. Efficiency of chemotherapy against adult worms was confirmed by the disappearance of circulating anodic antigen (CAA) in serum. Sandy patches showed resolution in two of four cases after chemotherapy. Papillomata due to schistosomiasis alone improved, but persisted in mixed infection with human papilloma virus (HPV) or when HPV was the only underlying cause. In one patient ulcera could not be related with certainty to schistosomiasis at admission, but resolved after treatment with parziquantel. Leukoplakia (two cases) was not influenced by chemotherapy, or even increased during follow-up, regardless of whether ova had been detected or not. Although the follow-up period was rather short, time intervals were not standardized, and a relatively small number of patients was investigated, it could be shown that genital pathology due to sequestered S. haematobium ova is, at least partially, reversible already two to nine weeks after killing the adult worms by praziquantel. This is paralleled by a normalization of inflammatory immune responses detectable in histological sections and vaginal lavage.

Female genital schistosomiasis (FGS): relationship between gynecological and histopathological findings

Schistosomiasis of the lower female reproductive tract manifests itself in a broad spectrum of clinical features. However, clinical and histopathological findings have never been studied in a synoptic manner. Based on the assumption that any type of pathology present in the female reproductive tract is the expression of a complex pathophysiological reaction towards eggs sequestered in the genital tissues, we decided to analyze colposcopic and histopathological findings in a comprehensive manner. Thirty-three women in Malawi with urinary and genital schistosomiasis were examined parasitologically and gynecologically. A thorough colposcopic examination with photodocumentation was performed and biopsies were taken from the cervix, the vagina and/or the vulva for histological sectioning and immunohistochemistry. The predominant colposcopic findings were sandy patches on the cervical surface similar to those seen in the bladder and polypous/papillomatous tumors with irregular surface on the vaginal wall and in the vulvar area. The histopathological sections of sandy-patch-like lesions demonstrated only a small cellular reaction around S. haematobium eggs in various stages of disintegration. In contrast, in the case of polyps the histology revealed a more pronounced immunological reaction characterized by a heavy cellular infiltrate. One case of invasive squamous cell carcinoma of the cervix was diagnosed. We conclude that colposcopy is a useful tool in the detection of FGS related pathology in the lower female reproductive tract and that the synoptic assessment of surface and of corresponding histological sections helped to understand the pathophysiology of S. haematobium associated disease in genital tissue.

Female genital schistosomiasis due to Schistosoma haematobium. Clinical and parasitological findings in women in rural Malawi

A total of 51 women with urinary schistosomiasis haematobium were examined in order to identify diagnostic indicators for female genital schistosomiasis (FGS). Patients were selected at random from the outpatient department of the Mangochi District Hospital, Malawi. The medical histories were recorded according to a pre-designed questionnaire and the women were subjected to a thorough gynaecological examination including colposcopy and photographic documentation of lesions. Microscopy of genital biopsies revealed that 33 of the 51 women had S. haematobium ova in cervix, vagina and/or vulva in addition to the presence of ova in urine. The most sensitive diagnostic procedure was beside microscopic examination of a wet cervix biopsy crushed between two glass slides, which revealed 25 of the 33 genital infections. There was a significant correlation between the size of genital lesions and the number of ova counted per mm2 of crushed tissue. Women with FGS had significantly more tumours in the vulva than women with schistosomiasis limited to the urinary tract. Most of the observed genital pathology could easily be identified by the naked eye, but colposcopic examination yielded valuable additional information like the demonstration of neovascularisation around cervical sandy patches. Few of the symptoms previously regarded as indicators for FGS could be linked to the presence of schistosome ova in genital tissue. Husbands of infertile women with FGS had children with other women significantly more often than husbands of women who only had urinary schistosomiasis. This, together with the finding that the majority of the divorced women had FGS, indicates that the manifestation of this disease may have implications for the marital and sexual life of the affected women.

Diagnosis of female genital schistosomiasis by indirect disease markers: determination of eosinophil cationic protein, neopterin and IgA in vaginal fluid and swab eluates

Based on assumptions about the pathophysiology of egg-related lesions in the lower reproductive tract, putative indirect disease markers were investigated in vaginal fluids from 54 Malawi adolescent girls and women infected with S. haematobium. These women received a careful gynecological examination during which biopsies were taken from the cervix, and, if present, also from suspicious lesions in the vagina and the vulva. If the biopsies, either in wet crushed preparations or in histological sections, contained eggs the patients were considered to have female genital schistosomiasis (FGS; n = 33). The remainder (n = 21) were classified as having urinary schistosomiasis only. Eosinophil cationic protein (ECP), a cytotoxic granule protein of eosinophils, neopterin, a second messenger molecule generated during the activation of macrophages, and IgA as an indicator of local B-cell activation were quantitatively determined in vaginal fluid. To clarify the origin of ECP, this protein was also looked for in histological sections by an immunohistochemical method. In order to explore whether such disease markers can be detected after absorption to a tampon-like material, ECP and IgA were also assessed after elution from a non-porous, polypropylene fibre web impregnated with vaginal fluid. The concentration of ECP in vaginal fluid and the degree of immunohistochemical staining in histological sections were significantly higher in patients with FGS than in women with urinary schistosomiasis only. The amount of ECP detected in histological sections correlated to the number of eggs/mm2 of compressed genital tissue (rho = 0.36, P = 0.02), and the concentration of ECP in vaginal fluid correlated to the concentration of neopterin as well as to that of IgA (rho = 0.52, P = 0.004 and rho = 0.37, P = 0.02, respectively). Median neopterin concentration in vaginal fluid was also higher in the FGS group, but the difference was not statistically significant. ECP could also be detected in eluates from impregnated fibre webs, but the concentration was approximately one power of 10 less than in the original vaginal fluid. These results demonstrate that indicators of immunological mechanisms related to the egg-granuloma might be useful as indirect disease markers for women with FGS if assessed in vaginal washings or swab eluates.

Optimization of the Magnetic Bead Antigen Capture Enzyme Immuno Assay for the detection of circulating anodic antigens in mixed Schistosoma infections

In the present study, simplification and adaptation of the Magnetic Bead Antigen Capture Enzyme Immuno Assay (MBAC-EIA) technique for detection of circulating anodic antigens (CAA) under field conditions was achieved. It was shown that the assay could be performed successfully within the broad temperature range of 18-37 degrees C. The slightly lower sensitivity observed at low temperatures could be adjusted for by prolonging the incubation period. Shaking the plate by hand was as good as automatic mechanical shaking, aspiration of the supernatant before the addition of conjugate was not necessary, and the use of whole blood and serum offered similar assay sensitivity. Furthermore incubation times could be considerably shortened without loss of sensitivity. A major advantage of the MBAC-EIA was that the beads, after elution of bound components, were found to be reusable. The study also showed that the sensitivity of the MBAC-EIA technique in diagnosis of schistosomiasis in a Zimbabwean community endemic for both urinary and intestinal schistosomiasis, was 94%.

[Typhoid fever]

The epidemiology, clinical presentation, diagnosis and treatment of typhoid fever has been studied retrospectively in 50 hospitalized patients. Typhoid fever is increasing in Norway, owing to more travel, especially by immigrants visiting their home countries. Among 50 patients admitted to hospital for typhoid, we found no fatal complications. Fever was a main symptom, and 13 of the 50 patients had additional concomitant infections. The standard treatment was chloramphenicol for 14 days. In 1990 and 1991, however, most cases were caused by multi-resistant strains of Salmonella typhi. The adults were therefore treated with ciprofloxacin and the children with third generation cephalosporins. All the multiresistant infections had been contracted in Pakistan or India. There were no secondary cases among the more than 214 family contacts in the 47 families involved. The increase in resistant strains of typhoid fever may affect future treatment and control strategies.

[Outbreak of typhoid fever in a family]

We describe a small epidemic of typhoid fever in a family who came originally from Pakistan. In 1992 six members (mother and five children) of a family of ten were admitted to our department with typhoid fever within a nine-day period. The index case was an 18 months old girl who had been hospitalized and treated elsewhere for typhoid fever. Two weeks after completing antibiotic treatment she was admitted to our hospital with a relapse. The source of her first infection is unknown. The rapid spread of typhoid fever in the family was most likely due to insufficient hygienic precautions and inadequate antibiotic treatment of the index case. Several coexisting factors such as poor housing conditions and cultural barriers may also have influenced the outcome. There is obviously a need for strict guidelines and proper coordination of treatment and follow-up of this and other similar contagious diseases.

[Resistance problems in developing countries--use and misuse of antiinfective agents]

Widespread use and misuse of antiinfectiva have resulted in a problem of drug resistance linked to treatment of infectious diseases. In developing countries especially, the sale of such drugs is poorly controlled and the pharmaceutical industry is dumping obsolete products. Intensive marketing, lack of diagnostic facilities and receptive local cultural attitudes to new "wonder drugs" such as antibiotics, have resulted in dramatic unnecessary use of such. Therefore the ideal strategies for treatment of infectious diseases guided by microbiological diagnosis and resistance pattern are violated in most developing countries, leading to excessive use of antiinfectiva and development of resistance. This has serious consequences for the infections that cause most cases of infant mortality, namely malaria, diarrhoeas and infections of the respiratory tract. Improvements in this vicious circle of drug use and resistance can only be made by attacking several factors simultaneously. There is a need for general information, stricter legislation, essential drug lists, national drug policies, better knowledge of local resistance patterns, better diagnostic facilities, better knowledge about local beliefs about drugs and better communication to local health workers and the community.

Magnetic bead antigen capture enzyme-linked immunoassay in microtitre trays for rapid detection of schistosomal circulating anodic antigen

We have developed a new magnetic bead antigen capture enzyme-linked immunoassay for the detection of schistosomal circulating anodic antigen. The assay utilizes IgG1 monoclonal antibody coated monodisperse magnetic beads in microtitre trays fitted to a special magnet. The total test time was found to be 1-2 h, using 0.05 mg beads per well. The lower detection level was 0.7 ng AWA-TCA per ml (approximately 0.07 ng CAA per ml). Validation by sera from uninfected and Schistosoma mansoni infected Africans and Norwegians resulted in an assay specificity of 100% and sensitivity was close to 90% for cases excreting more than 100 eggs per gram faeces. At such clinically relevant levels the inter-assay CV was below 10% and photometric absorbance correlated to antigen levels was nearly linear. There was a significant correlation between the magnetic bead EIA absorbance values and the titres obtained using the previously established ELISA. The new bead assay, however, was easier and less laborious because TCA pretreatment and the titration of positive results were unnecessary.

Quantitative detection of schistosomal circulating anodic antigen by a magnetic bead antigen capture enzyme-linked immunosorbent assay (MBAC-EIA) before and after mass chemotherapy

The magnetic bead antigen capture enzyme-linked immunosorbent assay (MBAC-EIA) has been applied to detect schistosomal circulating anodic antigen (CAA) in pre- and post-treatment sera from 55 individuals in a Schistosoma mansoni control project in the Blue Nile valley of western Ethiopia. The amounts of CAA detected by this assay were positively correlated with the numbers of eggs per gram of faeces (epg). A significant reduction in CAA levels as measured by the MBAC-EIA was observed after mass chemotherapy. The sensitivity was 88-89% in clinically significant cases excreting more than 100 epg. In light infections, however, the sensitivity was lower. None of 32 uninfected Norwegian blood donors or 12 Ethiopian immigrants to Norway were positive. The specificity was thus estimated to be 100%. The test is rapid (1-2 h) and simple to perform without sophisticated equipment and could therefore, with slight modification, be used as a reliable method of diagnosis at field level in endemic areas undergoing mass chemotherapy campaigns or population surveys.

Early detection of circulating anodic antigen (CAA) in a case of acute schistosomiasis mansoni with Katayama fever

A 34-year-old male developed acute Katayama fever with fever, diarrhoea, joint pains, headache, urticarial rash and eosinophilia 18 days after falling into and spending 15 min in the water during water-skiing in the outlet of the Volta river. Low anti-schistosomal antibody titres were found by the immunofluorescence assay after 4 weeks, and the first Schistosoma mansoni eggs were found in faeces after 6 weeks. Both symptoms and eosinophilia increased the first days after treatment with oxamniquine, after which he improved gradually. Examination of frozen sera by the newly developed Magnetic Beads Antigen Capture-EIA (MBAC-EIA) later demonstrated a peak in schistosomal circulating anodic antigen (CAA) levels of diagnostic significance already 4 weeks after he was infected.

[Clinical medicine in developing countries]

Clinical medicine in developing countries is often restricted in several ways due to factors such as lack of funds, trained personnel, diagnostic facilities and appropriate drugs. Clinical judgement, knowledge of the local epidemiological pattern and simple diagnostic and therapeutic procedures are crucial under such circumstances. Based on his own experience under primitive conditions in Ethiopia, the author gives some symptom-oriented differential diagnostic reflections and guidelines for simplified management of some major health problems in the tropics.

Control of Schistosoma mansoni in the Blue Nile Valley of western Ethiopia by mass chemotherapy and focal snail control: a primary health care experience

A simplified combination of human mass treatment with oxamniquine and focal snail control has been applied in a local Schistosoma mansoni control programme in a primary health care setting in the Dalati and Agallu Metti areas of the Ethiopian Blue Nile Valley. Teams of local health personnel and farmers did the daily work under intermittent supervision. Monthly snail surveys near the major villages disclosed a seasonal pattern with many infected snails during the dry season in upper stagnant sections of tributary rivers (1000-1200 m altitude) with favourable temperatures, and few snails in the rainy season. The highest prevalences and intensities of human infection were found in the 15-19 year age group living in the lower altitudes around 700 m. 5067 individuals (50-80% of the local population) were treated with 20-40 mg oxamniquine per kg body weight during the rainy seasons of 1985 (Dalati) and 1986 (Agallu Metti). In the Dalati area cross sectional surveys in 1985 and 1986, before and after the mass treatment, showed a reduction in prevalence from 42.4% to 11.4%, while in the Agallu Metti area a stratified random sample showed a prevalence reduction from 65.4% in 1986 to 7.8% in 1987 and a reduction in the prevalence of moderate to heavy infection (greater than 100 eggs per gram of stool) from 36.9% to 1.4%. Beginning in 1986 niclosamide was applied focally wherever infected snails were found and the monthly snail surveillance continued until 1989. As a result of this combined approach overall snail infection rates were reduced from 11.2% (Dalati) and 32% (Agallu Metti) to zero and 2% respectively. In 1989 the human prevalence was still only 8.6% in Agallu Metti. This programme has shown that it is feasible to control S. mansoni in these very remote localities through the primary health care system.

Severe erythroblastopenia and hemolytic anemia during a hepatitis A infection

A 41-year-old woman had acute hepatitis A infection complicated with severe anemia due to selective erythroblastopenia and hemolysis. A mechanism involving a cellular immune reaction is suggested. The hematological complications resolved during steroid treatment. She later developed a transient seropositive arthritis.

Onchocerciasis in the Blue Nile Valley of western Ethiopia

In a survey among 477 inhabitants of the Blue Nile Valley of western Ethiopia 182 (38%) were positive by skin snip investigation for microfilariae of Onchocerca volvulus. Of these only 23% had typical clinical signs and symptoms of onchocerciasis. The highest prevalence rate of microfilariae (84%) was found among Nilotics in the lowlands, where 50% of the children above 10 years, and 90% of adults above 30 years of age, were infected. The mean microfilarial density per skin snip was significantly higher in the high prevalence areas (14) than in the low prevalence areas (3). Positive skin snips from both hip and shoulder were found in 24% of the population, whereas 3% had microfilariae only in the shoulder and 11% only in the hip region. The mean microfilarial density in the hips (16) was double that in the shoulders (8). Ophthalmological evaluation, including slit lamp examination, was possible in 77 of the 182 cases with positive skin snips. Severe eye damage due to onchocerciasis was not observed. However, one 35 year old female had live microfilariae in the anterior chambers of both eyes.

Mezlocillin treatment of septicemia in general hospitals

Gramnegative septicemia in 23 patients from different Norwegian departments of general medicine or surgery was treated with mezlocillin. Most of the patients were old, and 14 patients were considered compromised due to underlying disease. In the majority of cases the septicemia originated from urinary tract infections. Uneventful recovery was accomplished in 16 patients (70%) and another 5 cases improved. In 2 patients no clinical effects were observed within 3 days of treatment. Apart from diarrhoea in 5 of the cases, no side-effects occurred. Mezlocillin proved to be a safe and efficient drug for the treatment of gramnegative septicemias of the type that is most commonly encountered in Norwegian general hospitals.

Rabies exposure among Norwegian missionaries working abroad

Based on the results of an inquiry among 296 Norwegian missionaries and Foreign Aid workers, we present some observations on the present rabies situation in several African countries, India and Bangladesh, Equador and Bolivia. Traditionally these countries receive a large proportion of our missionaries and Foreign Aid personnel. The incidence of rabies varies considerably in the areas covered by this investigation. When calculated for the mean length of stay (4 to 5 years) the average rating of physical exposure to proven or suspected rabies was 16% per household and 7% per individual household member. The risk of exposure was higher with children (10%) than adults (6%). the family dog equalled the stray dog as the source of suspected infection. Of the 48 persons who had been recommended post-exposure vaccination two thirds had only tended or been licked by the offending animal. However, in such animals the ratio of proven or highly probable rabies to non-proven or unknown diagnosis was 2:1. The rabies situation was considered as a minor factor of psychic stress by two thirds of the responding persons, even in highly epizootic countries. The results of this study may be of some value in the process of forming a policy for pre-exposure prophylaxis against rabies for people who are going to stay for a prolonged period of time in these areas of the world.