Sustained effectiveness of weekly iron-folic acid supplementation and regular deworming over 6 years in women in rural Vietnam

Background

Weekly iron-folic acid (IFA) supplementation and regular deworming is effective for the prevention of iron deficiency and anaemia in women of child-bearing age. Between 2006 and 2013, a program of weekly IFA and biannual deworming was implemented in Yen Bai province, Vietnam. In this study we aimed to determine the effectiveness of the program in reducing anaemia and the prevalence of hookworm infection after 72 months (six years).

Methods

This prospective cohort study followed up a cohort of 389 women of child-bearing age from baseline until six years after the introduction of the weekly IFA (one tablet containing 200 mg ferrous sulphate, 0.4mg folic acid) and deworming (one 400mg tablet of albendazole given twice yearly) program (May 2006 to 2012). In each of the six surveys (baseline and five follow-up surveys) we measured haemoglobin and ferritin, and the burden of soil transmitted helminth (STH) infections, and in the 72 month survey we also administered a questionnaire to assess adherence and possible impediments to participating in the program.

Results

Two hundred and fifty six (65.8%) of the original 389 women enrolled in the cohort attended the final 72 month survey. Haemoglobin levels were 122 g/L [95% C.I. 120, 124] at baseline and increased to 135g/L [95% C.I. 133, 138] after 72 months. The prevalence of anaemia was 37.8% [95% C.I. 31.0, 44.7] at baseline and reduced to 14.3% [95% C.I. 9.5, 19.1]. Hookworm infection prevalence, 75.9% [95% C.I. 68.1, 83.8] at baseline, reduced to 10.2% [95% C.I. 5.4, 15.0] with no moderate or heavy intensity infections. Seventy-two percent of participants reported still taking at least 75% of the weekly supplements, and 85.0% had taken the most recent deworming treatment.

Discussion

Anaemia rates fell significantly during the six-year program, and STH infections were eliminated as a public health risk. Adherence was well maintained but long-term sustainability is challenging in the absence of ongoing external support.

Weekly iron-folic acid (IFA) supplementation combined with regular deworming for women of child bearing age is effective in the prevention of iron deficiency and anaemia. Following a baseline survey, a weekly IFA and regular deworming project was implemented in Yen Bai province, Vietnam in 2006, and after 12 months expanded to the entire province. Haematological parameters, soil transmitted helminth (STH) burden and adherence to the program were monitored periodically until 2012. We found anaemia prevalence fell from 37.8% to 14.3% during the six-year period, and haemoglobin levels increased from 122 g/L to 135g/L. STH infections were essentially eliminated as a public health risk. Seventy-two percent of participants continued to take at least 75% of the weekly supplements, and 85.0% took the most recent deworming treatment. These results show that prevention of anaemia in women of child-bearing age with weekly IFA and regular deworming is feasible and effective over a prolonged period. However, long-term sustainability may be a major challenge in some settings in the absence of ongoing external support.

Elimination of iron deficiency anemia and soil transmitted helminth infection: evidence from a fifty-four month iron-folic acid and de-worming program

Background

Intermittent iron-folic acid supplementation and regular de-worming are effective initiatives to reduce anemia, iron deficiency, iron deficiency anemia, and soil transmitted helminth infections in women of reproductive age. However, few studies have assessed the long-term effectiveness of population-based interventions delivered in resource-constrained settings.

Methodology/Principal Findings

The objectives were to evaluate the impact of weekly iron-folic acid supplementation and de-worming on mean hemoglobin and the prevalence of anaemia, iron deficiency, and soil transmitted helminth infection in a rural population of women in northern Vietnam and to identify predictive factors for hematological outcomes. A prospective cohort design was used to evaluate a population-based supplementation and deworming program over 54 months. The 389 participants were enrolled just prior to commencement of the intervention. After 54 months 76% (95% CI [68%, 84%]) were taking the iron-folic acid supplement and 95% (95% CI [93%, 98%]) had taken the most recently distributed deworming treatment. Mean hemoglobin rose from 122 g/L (95% CI [120, 124]) to 131 g/L (95% CI [128, 134]) and anemia prevalence fell from 38% (95% CI [31%, 45%]) to 18% (95% CI [12%, 23%]); however, results differed significantly between ethnic groups. Iron deficiency fell from 23% (95% CI [17%, 29%]) to 8% (95% CI [4%, 12%]), while the prevalence of iron deficiency anemia was reduced to 4% (95% CI [1%, 7%]). The prevalence of hookworm infection was reduced from 76% (95% CI [68%, 83%]) to 11% (95% CI [5%, 18%]). The level of moderate or heavy infestation of any soil-transmitted helminth was reduced to less than 1%.

Conclusions/Significance

Population-based interventions can efficiently and effectively reduce anemia and practically eliminate iron deficiency anemia and moderate to heavy soil transmitted helminth infections, maintaining them below the level of public health concern.

Nutritional deficiencies are common in women in rural and disadvantaged regions, and, in particular, iron and folate deficiencies may impact their health and that of their offspring. Weekly iron-folic acid supplementation and regular deworming help to prevent these deficiencies, yet many women in developing countries do not have access to these interventions. Using the local health system, we implemented a weekly iron-folic acid supplementation program with regular deworming for approximately 250,000 women in a rural mountainous province of Viet Nam. We present the results of a survey of women's iron and worm infection status after the program has been running for 54 months. Overall, anemia prevalence fell from 38% to 18%, iron deficiency fell from 23% to 8% and the prevalence of iron deficiency anemia was reduced to 4%. The level of moderate or heavy infestation of any soil-transmitted worm infection was reduced to less than 1%. These results show that a health system-based program can reduce and maintain the prevalence of these diseases in the community at a level where they do not constitute a public health risk.

Prevalence and risk factors for symptoms of common mental disorders in early and late pregnancy in Vietnamese women: a prospective population-based study

BACKGROUND

Little is known about the prevalence of and risk factors for common mental disorders (CMD) in pregnant women in low-income countries. The aim of this study was to establish the prevalence of and psychosocial risk factors for clinically significant symptoms of CMD in early and late pregnancy in women in rural Viet Nam.

METHODS

A population-based sample of women was surveyed in early and late pregnancy. CMD were assessed by the Edinburgh Postnatal Depression Scale-Viet Nam Validation and psychosocial risks by study-specific structured interviews.

RESULTS

In total 497/523 (97%) eligible women were recruited and 419 (84%) provided complete data. Prevalence of CMD only in early pregnancy was 22.4% (95% CI 18.4-26.4); only in late pregnancy was 10.7% (95% CI 7.8-13.7) and at both assessment waves was 17.4% (95% CI 13.8-21.1). Non-economic and economic coincidental life adversity, intimate partner violence, past pregnancy loss, and childhood abuse were positively associated with persistent antenatal CMD. Older age, having a preference for the baby's sex, and nulli- or primiparity were risk factors for CMD in early pregnancy.

CONCLUSIONS

Persistent antenatal CMD are prevalent in rural areas of Viet Nam. Psychosocial risk factors play a major role in this significant public health problem.

Increased birth weight associated with regular pre-pregnancy deworming and weekly iron-folic acid supplementation for Vietnamese women

Background

Hookworm infections are significant public health issues in South-East Asia. In women of reproductive age, chronic hookworm infections cause iron deficiency anaemia, which, upon pregnancy, can lead to intrauterine growth restriction and low birth weight. Low birth weight is an important risk factor for neonatal and infant mortality and morbidity.

Methodology

We investigated the association between neonatal birth weight and a 4-monthly deworming and weekly iron-folic acid supplementation program given to women of reproductive age in north-west Vietnam. The program was made available to all women of reproductive age (estimated 51,623) in two districts in Yen Bai Province for 20 months prior to commencement of birth weight data collection. Data were obtained for births at the district hospitals of the two intervention districts as well as from two control districts where women did not have access to the intervention, but had similar maternal and child health indicators and socio-economic backgrounds. The primary outcome was low birth weight.

Principal Findings

The birth weights of 463 infants born in district hospitals in the intervention (168) and control districts (295) were recorded. Twenty-six months after the program was started, the prevalence of low birth weight was 3% in intervention districts compared to 7.4% in control districts (adjusted odds ratio 0.29, 95% confidence interval 0.10 to 0.81, p = 0.017). The mean birth weight was 124 g (CI 68 - 255 g, p<0.001) greater in the intervention districts compared to control districts.

Conclusions/Significance

The findings of this study suggest that providing women with regular deworming and weekly iron-folic acid supplements before pregnancy is associated with a reduced prevalence of low birth weight in rural Vietnam. The impact of this health system-integrated intervention on birth outcomes should be further evaluated through a more extensive randomised-controlled trial.

Low birth weight is an important risk factor for neonatal and infant morbidity and mortality and may impact on growth and development. Maternal iron deficiency anaemia contributes to intrauterine growth restriction and low birth weight. Hookworm infections and an iron-depleted diet may lead to iron deficiency anaemia, and both are common in many developing countries. A pilot program of deworming and weekly iron-folic acid supplementation for non-pregnant women aiming to prevent iron deficiency was implemented in northern Vietnam. We compared the birth weight of babies born to women who had had access to the intervention to babies born in districts where the intervention had not been implemented. The mean birth weight of the intervention districts' babies was 124 g more than the control districts' babies; the prevalence of low birth weight was also reduced. These results suggest that providing women with deworming and weekly iron-folic acid supplements before pregnancy is associated with increased birth weight in rural Vietnam. This intervention was provided as a health system integrated program which could be replicated in other at-risk rural areas. If so it could increase the impact of prenatal and antenatal programs, improving the health of both women and newborns.

Long-term weekly iron-folic acid and de-worming is associated with stabilised haemoglobin and increasing iron stores in non-pregnant women in Vietnam

Background

The prevalence of anaemia and iron deficiency in women remains high worldwide. WHO recommends weekly iron-folic acid supplementation where anaemia rates in non-pregnant women of reproductive age are higher than 20%. In 2006, a demonstration project consisting of weekly iron-folic acid supplementation and regular de-worming was set up in two districts in a northern province in Vietnam where anaemia and hookworm rates were 38% and 76% respectively. In 2008 the project was expanded to all districts in the province, targeting some 250,000 women. The objectives of this study were to: 1) examine changes in haemoglobin, iron stores and soil transmitted helminth infection prevalence over three years and 2) assess women's access to and compliance with the intervention.

Methods and Findings

The study was a semi-cross-sectional, semi-longitudinal panel design with a baseline survey, three impact surveys at three-, twelve- and thirty months after commencement of the intervention, and three compliance surveys after ten weeks, eighteen and thirty six months.

Results

After thirty months, mean haemoglobin stabilised at 130.3 g/L, an increase of 8.2 g/L from baseline, and mean serum ferritin rose from 23.9 µg/L to 52 µg/L. Hookworm prevalence fell from 76% to 22% over the same period. After thirty six months, 81% of the target population were receiving supplements and 87% were taking 75% or more of the supplements they received.

Conclusions

Weekly iron-folic acid supplementation and regular de-worming was effective in significantly and sustainably reducing the prevalence of anaemia and soil transmitted helminth infections and high compliance rates were maintained over three years.

Monitoring for Plasmodium falciparum drug resistance to artemisinin and artesunate in Binh Phuoc Province, Vietnam: 1998-2009

BACKGROUND

Artemisinin derivatives have been used for malaria treatment in Vietnam since 1989. Reported malaria cases have decreased from 1,672,000 with 4,650 deaths in 1991, to 91,635 with 43 deaths in 2006. Current national guidelines recommend artemisinin-based combination therapy (ACT), although artesunate is still available as monotherapy through the private sector. Recent reports suggest that effectiveness of ACT and artesunate monotherapy has declined in western Cambodia. This study examined Plasmodium falciparum resistance patterns over 10 years in southwest Vietnam in infected patients treated with artemisinin compounds.

METHODS

The study was conducted in two communes in Phuoc Long district, Binh Phuoc province, 100 km west of the Cambodian border. This was chosen as a likely site for emerging artemisinin resistance because of the high prevalence of P. falciparum malaria, and the length of time that artemisinin had been in use. In vivo and in vitro monitoring of P. falciparum susceptibility to anti-malarial drugs was conducted in 1998, 2001, 2004/5, and 2008/9. Patients with confirmed P. falciparum malaria received therapy with 5 or 7 days of artemisinin (1998 and 2001 respectively) or 7 days of artesunate

RESULTS

In the four surveys, 270 patients were recruited and treated. The mean parasite clearance times differed between 1998, 2001 and 2004/5 (1.8, 2.3 and 2.1 days, P < 0.01) but not between 1998 and 2008/2009. The mean parasite clearance times were correlated with parasite density at day 0 (r = 0.4; P < 0.001). Treatment failure rates after PCR adjustment were 13.8%, 2.9%, 1.2%, and 0% respectively. Susceptibility of P. falciparum to artemisinin in in vitro tests was stable during the period, except for a rise in EC90 and EC99 in 2001.

CONCLUSIONS

This study showed stable levels of P. falciparum sensitivity to artemisinin compounds in the two sites over a ten-year period. The introduction of ACT in this area in 2003 may have protected against the development of artemisinin resistance. Adherence to the latest WHO and Vietnamese guidelines, which recommend ACT as first-line therapy in all malarious areas, and continued monitoring along the Vietnam-Cambodia border will be essential to prevent the spread of artemisinin resistance in Vietnam.

Baseline iron indices as predictors of hemoglobin improvement in anemic Vietnamese women receiving weekly iron-folic acid supplementation and deworming

Iron deficiency anemia is highly prevalent among women living in rural Vietnam. However, the utility and cut-offs of indices for diagnosing iron deficiency anemia in the public health context is ill defined. We assessed the ability of iron indices to predict the hemoglobin response (HBR) to weekly iron-folic acid supplementation (WIFS) in anemic rural Vietnamese women. We compared hemoglobin, serum ferritin, and soluble transferrin receptor in a cohort of 221 non-pregnant women of reproductive age before and after 3 months of WIFS and deworming. At baseline, anemia (Hb < 120 g/L) was present in 81/221 (36.7%) of subjects. After 3 months, anemia prevalence fell to 58/221 (26.2%), and the mean hemoglobin change was +3.5 g/L (95% confidence interval, 0.9, 6.6). A hemoglobin response was observed in 50/75 (66.6%) of anemic women. A ferritin cut-off < 30 ng/mL was a more sensitive predictor of response than ferritin < 15 ng/mL.

A free weekly iron-folic acid supplementation and regular deworming program is associated with improved hemoglobin and iron status indicators in Vietnamese women

Background

Anemia due to iron deficiency is recognized as one of the major nutritional deficiencies in women and children in developing countries. Daily iron supplementation for pregnant women is recommended in many countries although there are few reports of these programs working efficiently or effectively. Weekly iron-folic acid supplementation (WIFS) and regular deworming treatment is recommended for non-pregnant women living in areas with high rates of anemia. Following a baseline survey to assess the prevalence of anemia, iron deficiency and soil transmitted helminth infections, we implemented a program to make WIFS and regular deworming treatment freely and universally available for all women of reproductive age in two districts of a province in northern Vietnam over a 12 month period. The impact of the program at the population level was assessed in terms of: i) change in mean hemoglobin and iron status indicators, and ii) change in the prevalence of anemia, iron deficiency and hookworm infections.

Method

Distribution of WIFS and deworming were integrated with routine health services and made available to 52,000 women. Demographic data and blood and stool samples were collected in baseline, and three and 12-month post-implementation surveys using a population-based, stratified multi-stage cluster sampling design.

Results

The mean Hb increased by 9.6 g/L (95% CI, 5.7, 13.5, p < 0.001) during the study period. Anemia (Hb<120 g/L) was present in 131/349 (37.5%, 95% CI 31.3, 44.8) subjects at baseline, and in 70/363 (19.3%, 95% CI 14.0, 24.6) after twelve months. Iron deficiency reduced from 75/329 (22.8%, 95% CI 16.9, 28.6) to 33/353 (9.3%, 95% CI 5.7, 13.0) by the 12-mnth survey, and hookworm infection from 279/366 (76.2%,, 95% CI 68.6, 83.8) to 66/287 (23.0%, 95% CI 17.5, 28.5) over the same period.

Conclusion

A free, universal WIFS program with regular deworming was associated with reduced prevalence and severity of anemia, iron deficiency and hookworm infection when made available to Vietnamese women over a 12-month period.

The effectiveness of 4 monthly albendazole treatment in the reduction of soil-transmitted helminth infections in women of reproductive age in Viet Nam

Soil-transmitted helminth (STH) infections are endemic in northern Viet Nam where the climate and agricultural practices, such as the use of human excreta as fertiliser and the use of wastewater for irrigation, favour transmission. An intervention was conducted in Yen Bai Province, north-west Viet Nam, to measure the effectiveness of single dose albendazole (400mg) administered every 4 months for reducing the prevalence of STH infections in women of reproductive age. Stool samples were collected from women before the intervention and 3 and 12 months post-intervention. Information on a range of demographic and socio-economic variables was also collected to measure the major risk factors for high STH burden in this area. The prevalence of hookworm, Ascaris lumbricoides and Trichuris trichiura infection in the baseline sample of 366 women were 76.2%, 19.2% and 29.1%, respectively. In the women who were surveyed at baseline and again at 3 and 12 months after the intervention (n=118) cure rates were 71.3% for hookworm, 87.0% for A. lumbricoides and 81.4% for T. trichiura by the end of the 12 month study period (i.e. after three doses of albendazole). The main risk factor for hookworm infection was if women worked outside (odds ratio (OR)=3.2 (95% Confidence Interval (CI) 1.6-6.2), P=0.001) and the major risk factor for A. lumbricoides and T. trichiura infection was a lack of education. Low educational attainment was also the strongest risk factor for co-infection with all three species of STH (OR=7.5 (95% CI 3.4-16.4), P<0.001). The high rates of hookworm infection in this area of Viet Nam and the high cure rates for all three species of STH with 4 monthly albendazole treatment suggest that this programme should be expanded to all endemic areas in Viet Nam. The study also highlights the important contribution of education to women's health.

Anemia, iron deficiency, meat consumption, and hookworm infection in women of reproductive age in northwest Vietnam

Iron deficiency anemia poses an important public health problem for women of reproductive age living in developing countries. We assessed the prevalence of iron deficiency and anemia and associated risk factors in a community-based sample of women living in a rural province of northwest Vietnam. A cross-sectional survey, comprised of written questionnaires and laboratory analysis of hemoglobin (Hb), ferritin, transferrin receptor, and stool hookworm egg count, was undertaken, and the soluble transferrin receptor/log ferritin index was calculated. Of 349 non-pregnant women, 37.53% were anemic (Hb < 12 g/dL), and 23.10% were iron deficient (ferritin < 15 ng/L). Hookworm infection was present in 78.15% of women, although heavy infection was uncommon (6.29%). Iron deficiency was more prevalent in anemic than non-anemic women (38.21% versus 14.08%, P < 0.001). Consumption of meat at least three times a week was more common in non-anemic women (51.15% versus 66.67%, P = 0.042). Mean ferritin was lower in anemic women (18.99 versus 35.66 ng/mL, P < 0.001). There was no evidence of a difference in prevalence (15.20% versus 17.23%, P = 0.629) or intensity (171.07 versus 129.93 eggs/g, P = 0.412) of hookworm infection between anemic and non-anemic women. Although intensity of hookworm infection and meat consumption were associated with indices of iron deficiency in a multiple regression model, their relationship with hemoglobin was not significant. Anemia, iron deficiency, and hookworm infection were prevalent in this population. Intake of meat was more clearly associated with hemoglobin and iron indices than hookworm. An approach to addressing iron deficiency in this population should emphasize both iron supplementation and deworming.

Molecular epidemiology of Plasmodium falciparum resistance to antimalarial drugs in Indonesia

The extent of gene polymorphisms associated with resistance to chloroquine and sulfadoxine-pyrimethamine was examined in field isolates of Plasmodium falciparum from Indonesia. Eight malaria-endemic areas, representing a broad region of the western and eastern Indonesian Archipelago were surveyed. Blood from 20-50 patients was collected at each site, DNA was isolated, and the sequences of four different genes (dihydrofolate reductase [dhfr], dihydropteroate synthase [dhps], P. falciparum multidrug resistance 1 [pfmdr1], and P. falciparum chloroquine resistance transporter [pfcrt]) were analyzed using polymerase chain reaction and restriction fragment length polymorphisms to detect polymorphisms previously shown to be associated with resistance. This analysis identified polymorphisms in dhfr at 108-Asn/Thr, 16-Val, and 59-Arg. Polymorphisms in dhps were found less frequently, either 437-Gly alone or paired with 540-Glu. The pfcrt 76-Thr polymorphism was fixed in all parasite populations and pfmdr1 86-Tyr polymorphisms in all populations except in the most eastern regions. The pfmdr1 1042-Asp polymorphism occurred less frequently. These findings indicate that polymorphisms in genes associated with drug resistance in P. falciparum are found across a broad region of Indonesia.

Molecular analysis of Plasmodium falciparum from drug treatment failure patients in Papua New Guinea

A study was conducted in Papua New Guinea to analyze Plasmodium falciparum drug resistance polymorphisms in patients presenting with resistant malaria. One hundred ninety-nine P. falciparum-positive patients were recruited at two sites, Madang and Maprik. Exposure to the 4-aminoquinolines chloroquine and amodiaquine was uniformly high, at 84% overall. However, 59% of these were taken in various combinations of sulfadoxine/pyrimethamine and/or primaquine and/or quinine. Two markers for 4-aminoquinoline resistance, P. falciparum chloroquine resistance transporter 76T and P. falciparum multidrug resistance 1, were fixed in the population and two markers for pyrimethamine resistance, dihydrofolate reductase (dhps) 59R and 108N, were found at moderate to high levels, overall 60% and 75%, respectively. No polymorphisms in dhps associated with sulfadoxine resistance were present. Differences between the two sites are analyzed. The study period encompasses a change in standard malaria treatment policy. These findings stress the need for regular monitoring of the effects of standard drug treatment of uncomplicated malaria in Papua New Guinea.

New haplotypes of the Plasmodium falciparum chloroquine resistance transporter (pfcrt) gene among chloroquine-resistant parasite isolates

Mutations in the Plasmodium falciparum chloroquine resistance transporter (pfcrt) gene were examined to assess their associations with chloroquine resistance in clinical samples from Armopa (Papua) and Papua New Guinea. In Papua, two of the five pfcrt haplotypes found were new: SVIET from Armopa and CVIKT from an isolate in Timika. There was also a strong association (P < 0.0001) between the pfcrt 76T allele and chloroquine resistance in 50 samples. In Papua New Guinea, mutations in the pfcrt gene were observed in 15 isolates with chloroquine minimum inhibitory concentrations (MICs) of 16-64 pmol, while the remaining six isolates, which had a wild-type pfcrt gene at codon 76, had MICs of 2-8 pmol. These observations confirm that mutations at codon 76 in the pfcrt gene are present in both in vivo and in vitro cases of chloroquine resistance, and that detection of the pfcrt 76T allele could predict potential chloroquine treatment failures.

Mutations in the pfmdr1, dhfr and dhps genes of Plasmodium falciparum are associated with in-vivo drug resistance in West Papua, Indonesia

This study (conducted in 1996-99) examines the association of mutations in pfmdr1, dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) genes of Plasmodium falciparum with in-vivo drug resistance in West Papua, Indonesia. Initially, 85 patients infected with P. falciparum were treated with chloroquine, of whom 21 were cleared of parasites, 49 had parasitaemias classified as RI, RII or RIII resistance and 1 patient had recrudescent parasitaemia. Fansidar (pyrimethamine-sulfadoxine) was the second-line treatment and 18 patients were cleared of parasites and 31 had continuing infections classified as RI, RII or RIII resistance and 1 patient had recrudescent parasitaemia. The pfmdr1, dhfr and dhps genes were examined for mutations previously shown to be associated with resistance to these drugs. In this study, mutations in pfmdr1 were associated with chloroquine resistance and mutations in both dhfr and dhps were associated with Fansidar resistance in vivo. Interestingly, Gly-437 in dhps along with Arg-59/Asn-108 in dhfr were associated with RI, RII and RIII resistance whereas Glu-540 was highly associated with only RII and RIII Fansidar resistance. This finding supports the hypothesis that the molecular basis of RI, RII and RIII Fansidar resistance involves an accumulation of mutations in both dhfr and dhps. These results suggest that mutations in both dhfr and dhps genes are a good predictor of potential Fansidar treatment failure.

Grandpaternal mosaicism in a family with isolated haemophilia A

About one third of cases of haemophilia A have no family history of the disorder, and 20% are thought to be due to a new mutation. In the family reported here, a 3 bp deletion was detected in DNA from the proband at the 3' end of exon 15. Direct sequencing of genomic DNA prepared from blood and buccal cells of the grandfather revealed both normal and mutant sequences, suggesting that he is a mosaic for this mutation. This highlights the usefulness of mutation detection, both for accurate genetic counselling and to determine the origin of new mutations of haemophilia.

Direct mutation analysis as the preferred method for carrier diagnosis in families with isolated cases of haemophilia B

Approximately one-third of haemophilia B cases are described as isolated due to their occurrence in families with no prior history of the disorder. In this report, two families with isolated haemophilia B were studied by the standard method of restriction fragment length polymorphism (RFLP) analysis coupled with factor IX activity and antigen levels with the aim of achieving carrier diagnoses. The limitations of using this approach in the determination of carrier status were highlighted by diagnostic problems arising in both families. The problems included difficulty in interpreting bioassay results, homozygosity for the RFLP marker in a key family member and the possibility of germline mosaicism. Unequivocal carrier diagnosis in the two families was ultimately achieved by direct mutation analysis.

Mutations in a subgroup of patients with mild haemophilia A and a familial discrepancy between the one-stage and two-stage factor VIII:C methods

A subgroup of patients with haemophilia A who have a familial discrepancy between the one-stage and two-stage factor VIII:C results has previously been described. These patients show factor VIII:C levels by one-stage assay that are 2-7-fold higher than their two-stage results. We have studied 10 such families and identified six different mutations in the factor VIII gene in this group. The chemical cleavage method and DNA sequencing was used to identify mutations in factor VIII gene fragments generated by reverse transcription and PCR. All available family members were tested to confirm the presence of the mutation in affected individuals. These patients were found to have one of six single point substitutions causing a missense mutation and alteration to one codon in exons 7, 11, 14 or 18. The mutations comprise three that have not previously been described (Ala284Glu. Arg698Leu. Leu1932Phe) and three that have been previously described (Ser289Leu, Arg531His, Arg698Trp). Alterations to the amino acid composition of the A1, A2 and A3 domains of factor VIII are predicted by these molecular studies. In contrast, a control group of 23 mild haemophilia families with equivalent factor VIII:C results by one-stage and two-stage assays did not have any of the above mutations. Detailed studies in seven of these latter families identified four mutations affecting the A3, C1 and C2 domains of factor VIII. These findings suggest a genetic basis to the unusual factor VIII phenotype but do not explain the mechanism of the discrepant factor VIII activity.

Some haematological and physical characteristics of a group of Papua New Guinea highlanders

Full blood counts and some serum biochemistry were carried out on 349 male and 22 female apparently healthy Papua New Guinea subjects, most of whom were highlanders. In males, RBC, Hb, PCV, MCH, MCHC, serum albumin, ferritin, iron, per cent transferrin saturation and folate means were significantly lower than the Australian normal means; WBC and MCV means were similar to Australian values; and eosinophil and reticulocyte counts and serum transferrin and vitamin B12 means were higher than Australian means. In females, WBC, RBC, Hb, PCV, MCV, MHC, MCHC and serum ferritin means were lower than Australian means; eosinophil counts, serum iron, per cent transferrin saturation, and folate means were similar to Australian means; and serum transferrin and B12 means were higher than the Australian means. Hepatomegaly and mild splenomegaly were common. beta-Thalassemia was present in three subjects two of whom were from Simbu Province.

The relationship of hookworm infection, anaemia and iron status in a Papua New Guinea highland population and the response to treatment with iron and mebendazole

In 345 apparently healthy Papua New Guinea male subjects, predominantly highlanders, 89% of whom were infected with hookworm (Necator americanus), there was a statistically significant inverse correlation of hookworm egg count with haemoglobin and serum ferritin level, but no significant correlation with serum albumin, folate or B12 values. A sub-group of 128 was chosen for a six-month study on the effect of treatment with the anthelmintic mebendazole and/or parenteral iron on haemoglobin and serum ferritin levels. Mebendazole-treated subjects remained worm-free and the hookworm egg counts of the controls decreased during the study period. Parenteral iron treatment had the expected effect of raising haemoglobin to a normal level. There was a statistically significant improvement in haemoglobin level in all treated groups but not in the control. Serum ferritin levels decreased significantly in all groups, but more in the control than in the treated groups, although treatment groups were not significantly different. Although probable inadequate uptake of iron by the subjects and blood donation by some subjects was apparently more detrimental to iron status than hookworm infection, the results of this study support the view that hookworm infection in this country contributes to lowered haemoglobin levels and iron status.