Detection of enteric viral and bacterial pathogens associated with paediatric diarrhoea in Goroka, Papua New Guinea.

OBJECTIVES: The aim of this study was to investigate the viral and bacterial causes of acute watery diarrhoea in hospitalized children in Papua New Guinea. METHODS: A retrospective analysis was conducted on stool samples collected from 199 children (age <5 years) admitted to the paediatric ward of Goroka General Hospital from August 2009 through November 2010. A large range of viral and bacterial enteric pathogens were targeted using real-time PCR/RT-PCR assays. RESULTS: Young children were much more likely to be admitted with acute gastroenteritis, with 62.8% of patients aged <1 year and 88.4% aged <2 years. An enteric pathogen was detected in 69.8% (n=138) of patients. The most commonly detected pathogens were Shigella spp (26.6%), rotavirus (25.6%), adenovirus types 40/41 (11.6%), enterotoxigenic Escherichia coli (11.1%), enteropathogenic E. coli (8.5%), norovirus G2 (6.0%), and Campylobacter spp (4.0%). Norovirus G1, sapovirus, and Salmonella spp were also detected, but below our statistical limit of detection. Vibrio cholerae and astrovirus were not detected in any patients. Mixed infections were detected in 22.1% of patients, with Shigella and rotavirus most commonly detected in co-infections with other pathogens. CONCLUSIONS: This study demonstrates that Shigella and rotavirus are the major pathogens associated with acute paediatric gastroenteritis in this setting.

Is human malarial coma caused, or merely deepened, by sequestration?

Much research into falciparum malaria coma assumes the primary event to be vascular obstruction by parasitized red blood cells. Recent evidence that vivax malaria, caused by a parasite traditionally thought not to block blood flow, seems to alter brain function to the same degree as falciparum malaria has seriously questioned this. These data are a timely call to reassess whether vascular obstruction should still be considered the primary cause of the coma of falciparum disease. They add to a growing literature that suggests that enhancement of brain-origin cytokines, such as tumour necrosis factor, by non-brain systemic inflammation and an appreciation of the degree to which neuronal homeostasis depends on them provide a more fruitful research direction.

Application of respondent driven sampling to collect baseline data on FSWs and MSM for HIV risk reduction interventions in two urban centres in Papua New Guinea.

The need to obtain unbiased information among hard-to-reach and hidden populations for behavioural and biological surveillance, epidemiological studies, and intervention program evaluations has led researchers to search for a suitable sampling method. One method that has been tested among IDU and MSM recently is respondent-driven sampling (RDS). We used RDS to conduct a behavioural survey among FSWs and MSM in two urban centres in Papua New Guinea (PNG). In this paper we present the lessons learned implementing RDS in a developing country setting. We also present comparisons of RDSAT-adjusted versus unadjusted crude estimates of some key socio-demographic indicators as well as comparisons between the estimates from RDS and a hypothetical time-location sample (TLS). Overall, the use of RDS among the MSM and FSWs in PNG had numerous advantages in terms of collecting a required sample size in a short time period, minimizing costs and maximising security for staff and respondents. Although there were a few problems these were easily remedied and we would recommend RDS for other similar studies in PNG and other developing countries.

Low birthweight at a Papua New Guinea highlands hospital.

A prospective case-control study involving 75 low birthweight (LBW) babies and 224 controls was carried out at the Mount Hagen General Hospital over a period of 7 months, from June to December 1997. Identified risk factors for LBW in this population included maternal age (age less than 22 years or over 35 years, p = 0.03), a birth interval of less than 2 years (p = 0.006), no antenatal booking (p = <0.005), low attendance at antenatal clinic (p = <0.005), fever during pregnancy (p = <0.005), PET (p = 0.05), APH (p = <0.015), and maternal smoking during pregnancy (p = 0.008). Other well-established risk factors for LBW, i.e. small stature, low body mass index (BMI), haemoglobin less than 8 g/dl, and low educational attainment, appeared to be more frequent in the mothers of the LBW babies than the controls but differences did not reach statistical significance. The results suggest the need for improved provision of, and efforts to increase the use of, antenatal and family planning services. The results also provide clear evidence of the deleterious effects of smoking during pregnancy in a developing country.

Adult head and neck lymphomas in Papua New Guinea: a retrospective study of 70 cases.

BACKGROUND: During a 10-year period (1986-95), 70 adult Papua New Guineans with head and neck lymphomas were seen in the 18 years-and-above age group. METHODS: The clinical information was obtained from the medical records section of the Port Moresby General Hospital. Relevant treatment modalities and the follow-up data were acquired from the National Cancer Centre, Angau Memorial Hospital, Lae. RESULTS: Of a total of 227 adult lymphomas recorded in a 10-year period, 70 cases were seen in the head and neck region. Non-Hodgkin's lymphoma constituted 56 cases, which included seven cases of adult Burkitt's-like lymphoma. Fourteen cases of Hodgkin's lymphoma were recorded. CONCLUSIONS: In Papua New Guinea, malignant lymphomas primarily affecting the head and neck region were seen in 30.8% of all lymphomas. This constitues 2.8% of all malignancies in this region. These lymphomas appear to be more aggressive at this site. Proper tissue diagnosis and combination chemoradiotherapy are the key factors in its management.

Epstein-barr virus nuclear antigen 1 sequences in endemic and sporadic Burkitt's lymphoma reflect virus strains prevalent in different geographic areas.

The Epstein-Barr virus (EBV) nuclear antigen EBNA1 is the only viral protein detectably expressed in virus genome-positive Burkitt's lymphoma (BL); recent work has suggested that viral strains with particular EBNA1 sequence changes are preferentially associated with this tumor and that, within a patient, the tumor-associated variant may have arisen de novo as a rare mutant of the dominant preexisting EBV strain (K. Bhatia, A. Raj, M. J. Gutierrez, J. G. Judde, G. Spangler, H. Venkatesh, and I. T. Magrath, Oncogene 13:177-181, 1996). In the present work we first study 12 BL patients and show that the virus strain in the tumor is identical in EBNA1 sequence and that it is matched at several other polymorphic loci to the dominant strain rescued in vitro from the patient's normal circulating B cells. We then analyze BL-associated virus strains from three different geographic areas (East Africa, Europe, and New Guinea) alongside virus isolates from geographically matched control donors by using sequence changes in two separate regions of the EBNA1 gene (N-terminal codons 1 to 60 and C-terminal codons 460 to 510) to identify the EBNA1 subtype of each virus. Different geographic areas displayed different spectra of EBNA1 subtypes, with only limited overlap between them; even type 2 virus strains, which tended to be more homogeneous than their type 1 counterparts, showed geographic differences at the EBNA1 locus. Most importantly, within any one area the EBNA1 subtypes associated with BL were also found to be prevalent in the general population. We therefore find no evidence that Burkitt lymphomagenesis involves a selection for EBV strains with particular EBNA1 sequence changes.

A study of substance abuse on two campuses of University of Papua New Guinea.

BACKGROUND: Recent research reports indicate that there is a substantial amount of substance abuse on the campuses of the University of Papua New Guinea. OBJECTIVE: To compare the frequency and quantity of alcohol and drug abuse on the two campuses of the University of Papua New Guinea in the National Capital District. METHODS: A purposely designed questionnaire was used to collect data randomly on a total of 90 subjects (45 from each campus). The data was subjected to computer analysis. RESULTS: The results show that abuse of alcohol, tobacco and other drugs is prevalent on the two campuses of the University of Papua New Guinea. CONCLUSION: The results will form the basis of recommendations for substance abuse prevention, through information and education of the University students and staff members.

Relation of anthropometry to malaria morbidity and immunity in Papua New Guinean children.

The interaction between malnutrition and malaria is complex and there is evidence that malnutrition decreases the susceptibility to malaria. To investigate the relation between anthropometric measurements and subsequent malaria morbidity and to examine whether the effect observed was due to interaction with host immunity, we followed for 1 y a cohort of 136 children aged 10 to < 120 mo in Wosera, East Sepik Province, Papua New Guinea. At baseline, 21% were stunted, 10% were wasted, and 5% were both stunted and wasted. After adjustment for age and use of bed nets, height-for-age z score (HAZ) at baseline predicted the number of clinical episodes of falciparum malaria during the following year: incidence rate increased with increasing HAZ. Humoral responses to specific malarial antigens were lowest in the wasted children. The prevalence of lymphoproliferative responders was not significantly different between well-nourished and undernourished children. In contrast, the prevalence of cytokine producers was higher in the undernourished than in the well-nourished children. Our findings support the view that stunting but not wasting protects against falciparum malaria. The mechanism may be related to an improved ability of malnourished children to produce certain cytokines in response to stimulation by specific malarial antigens.

The prevalence of surface antigen variants of hepatitis B virus in Papua New Guinea, South Africa, and Sardinia.

Three assays, one based on monoclonal antibodies and the others on polyclonal antibodies, were employed to detect hepatitis B surface antigen (HBsAg)-reactive samples in both vaccinated and unvaccinated populations in areas of the world where hepatitis B virus (HBV) is endemic. Any discordant sera were tested by polymerase chain reaction (PCR) to confirm current infection, and sequence data were obtained from the DNA coding for the major hydrophilic region (MHR) of HBsAg of those samples positive for PCR. In all countries studied, samples that reacted in one HBsAg assay but not another were found. In the most extreme case, about 5% of viremic sera in Papua New Guinea were nonreactive in the monoclonal HBsAg assay; 9 of the 13 PCR-positive samples had novel or once-described variants, or a variant out of its usual genotype context. In South Africa, samples with sequences of subtype ayw2 reacted poorly, particularly in the polyclonal assay. Two had novel variants. In Sardinia, antibody to hepatitis B core antigen (anti-HBc) was analyzed as a marker of infection. A significant proportion of anti-HBc-positive, but monoclonal HBsAg-negative, vaccinees and unvaccinated persons were found to be PCR positive, as were some individuals without any markers of hepatitis B virus infection. Five more novel variants were found in these groups. There are implications for the design of HBsAg assays, which may have to be modified according to local sequence variability. Not all discordant samples were explained by variants, indicating that assay sensitivity is fundamental to diagnostic efficacy. Overall, this study defined 16 novel variants and 2 new potential epitope clusters.

Effects of low calcium and magnesium dietary intake on the central nervous system tissues of rats and calcium-magnesium related disorders in the amyotrophic lateral sclerosis focus in the Kii Peninsula of Japan.

Current epidemiological investigations in the Western Pacific including the Kii Peninsula of Japan, have suggested that environmental factors contribute to the pathogenetic process of amyotrophic lateral sclerosis (ALS) and parkinsonism dementia (PD). The condition of unbalanced minerals (a low content of calcium and magnesium, and a high content of aluminum) found in soil and drinking water in all three ALS foci was experimentally mimicked in our studies using rats. In rat groups maintained on unbalanced mineral diets, the calcium and magnesium contents of bones were lower than those fed a standard diet. In addition, the calcium content of CNS tissues showed higher values in the unbalanced diet groups (especially in the spinal cord of the low calcium and magnesium plus high aluminum diet group) than those in the standard diet group. The calcium content of other soft tissues as well as the CNS of rats fed unbalanced mineral diets was also higher than those on the standard diet. The magnesium content of soft tissues and spinal cord of rats was markedly lower in the low calcium and magnesium plus high aluminum diet group than in the other groups. Examination of tissues from six Kii Peninsula patients with ALS showed an average magnesium concentration in 26 CNS regions (cortical gray matter, white matter, basal ganglia, brain stem, spinal cord) significantly lower than that for five neurologically normal controls. The average calcium concentration in gray matter of ALS cases was significantly higher than that of controls. Interestingly, only 120 cases of calcification of spinal ligaments have been reported worldwide, and of these, 26 of 28 cases of calcification of spinal in the Kii Peninsula have been found to overlap the same geographic focal region as ALS. We analyzed the magnesium content of seven spinal vertebrae and 10 spinal ligaments of patients with calcification of spinal ligaments and the calcium content of five spinal bones compared with controls. The calcification of spinal ligaments patients had lower values for magnesium contents of bones and ligaments compared to controls and the calcium content of bones in these patients was significantly lower than that of controls. These data suggest that low dietary intake of calcium and magnesium over an extended period of time may contribute to the pathogenesis of patients with ALS and calcification of spinal ligaments.

A retrospective survey of patients with one previous caesarean section delivered at the Port Moresby General Hospital: a comparative study of those delivered vaginally and those delivered by repeat caesarean section.

We studied 510 patients in a retrospective, nonrandomized, comparative survey of vaginal births and repeat caesarean section after one primary caesarean section at the Port Moresby General Hospital. 478 (94%) were allowed a trial of scar (TOS). The most common indications for elective caesarean section in the other 32 patients were cephalopelvic disproportion (CPD) 31%, contracted pelvis 19% and preeclampsia 12.5%. In 41% of patients TOS was terminated by emergency caesarean section. Logistic regression analysis showed that the following were significantly associated with repeat caesarean section after TOS: parity of one, no vaginal birth after the primary caesarean section, narrow obstetric conjugate, birthweight of 2500 g or greater, short stature, high level of the head at admission to the labour ward and region of origin.

Trauma admissions in the southern highlands of Papua New Guinea.

BACKGROUND: Trauma is a common cause of surgical admission in Papua New Guinea (PNG) but to date there has been no study of the whole trauma burden in provincial hospitals. METHODS: A 1-year retrospective study was made of all surgical admissions to the provincial hospital at Mendi. RESULTS: Trauma was the third commonest reason for hospital admission and accounted for 43% of all surgical cases. The common causes of injury were tribal fights (24%), domestic violence (14.3%), assault (16.7%), road accidents (14%) and domestic accidents (25.1%), which comprised falls, penetrating wounds and bites. Males accounted for two-thirds of cases, and 19% were children below the age of 16. Only eight of 454 patients died (1.8%), because most trauma deaths occur before the patient reaches hospital. There were only 37 multiple injuries and only five patients had an injury severity score of greater than 16. The average inpatient stay for trauma admissions was 10.6 days. CONCLUSIONS: The cost of trauma in Mendi is difficult to calculate, but is enormous. In addition to 11% of the recurrent hospital expenditure (over US$1.1 million, excluding pharmaceuticals), the community costs include loss of earnings and productivity, as well as permanent disability. The social disruption caused by tribal fights results in cessation of the local economy, burning of aid posts, schools and homes and destruction of gardens for subsistence farming. Those who reach hospital alive tend to have single injuries and survive.

Otitis media with effusion in children: an audiological case series study.

Otitis media with effusion (OME) was studied in detail in 100 children seen at the Ear, Nose and Throat (ENT) Clinic of Port Moresby General Hospital (PMGH) between June 1992 and June 1994. More males were examined than females. The majority of patients were from the National Capital District and Central Province. Pure-tone and impedance audiometry were performed to assess the type, amount and pattern of hearing loss. A characteristic audiogram for OME with improved air conduction (AC) and decreased bone conduction (BC) hearing at 2 KHz and AC loss at both low and high frequencies was established. Bilateral myringotomy and grommet insertion was performed in 30 of these children. Significant improvement in hearing threshold at all frequencies was found, indicating hearing success with surgery. Otitis media with effusion is a disease of considerable public health importance and there is a need to increase public and professional awareness of it in Papua New Guinea.

Venom detection kits in the management of snakebite in Central province, Papua New Guinea.

The bites of six species of venomous elapid snakes in Central Province Papua New Guinea produce similar clinical syndromes. Optimal management of envenomed patients involves the use of monospecific antivenom. In this study, Venom Detection Kits (VDKs) (CSL Diagnostics, Melbourne) were used to try to make a specific diagnosis in envenomed patients at their admission. VDKs detected venom in admission bite site swabs from 39 to 46 patients (85%). Thirty-eight of these patients were shown to have been bitten by taipans. In all cases where venom was detected by the VDK, this correlated with subsequent laboratory enzyme immunoassay results. Selective use of VDKs in Central Province could allow more widespread use of monospecific antivenoms and produce considerable financial savings.

Liver disease in Papua New Guinea 1981 to 1988, twenty years after the first surveys were done.

Twenty years after the first surveys of liver disease were done cirrhosis and hepatocellular carcinoma were still found to be the most important liver diseases in Papua New Guinea. Hepatitis B virus appears to be the main cause of both these conditions. Data from a number of different sources suggest a prevalence of hepatitis B positivity of about 17%. The most significant new finding was grade 3 iron deposition in 8 patients. This raises the question as to whether iron storage disease may now contribute to the spectrum of liver disease in Papua New Guinea. Many biopsies in the 1960s and 1980s were interpreted as nonspecific hepatitis; in the light of recent observations, at least some of these may have been due to hepatitis C infection.

Heterogeneity within the Epstein-Barr virus nuclear antigen 2 gene in different strains of Epstein-Barr virus.

DNA isolated from biopsies of endemic Burkitt's lymphoma (BL) from New Guinea was analysed for the presence of Epstein-Barr virus (EBV) sequences using the polymerase chain reaction. Primers were designed to amplify sequences within the Epstein-Barr virus nuclear antigen (EBNA) 1 and 2 genes. These analyses detected the EBNA1 sequence in all the biopsies studied. Additional sets of primers directed against the EBNA2 gene were used in order to categorize the EBV strains as A-type or B-type (39% A-type; 50% B-type; 5% A- and B-type; 5% untypeable). These results indicated that DNA sequence heterogeneity within the EBNA2 gene region may exist in different strains of EBV. The extent of DNA sequence heterogeneity among different strains of EBV was determined by sequencing of a region within the EBNA2 gene in a number of different A-type and B-type strains of EBV originating from Africa or New Guinea. The results demonstrated DNA sequence heterogeneity within the EBNA2 gene in different strains of EBV. This heterogeneity was more extensive among A-type strains than B-type strains of EBV.

Estudos de intervençäo sobre vacinaçäo BCG em hanseníase: uma análise comparativa / Trial studies about BCG vaccination against leprosy: a comparative analysis

De um total de 468 trabalhos publicados sobre BCG e Hanseníase, os autores selecionaram três trabalhos realizados em Uganda, Nova Guiné e Birmânia, para análise comaprativa. Foram estudados segundo populaçäo de referência; de estudo; critérios de participaçäo e locaçäo; programas oferecidos aos participantes e avaliaçäo. Encontrou-se uma eficácia que variou de 20 a 80 por cento. Diferenças metodológicas na escolha de populaçöes (referência/estudo) e/ou critérios (participaçäo/locaçäo/avaliaçäo) poderiam, entre outras causas, contribuir para explicar as diferentes eficácias encontradas