By 2009, there were worrying signs from western Cambodia that parasitological responses to artesunate-containing treatment regimens for uncomplicated Plasmodium falciparum malaria were slower than ...elsewhere which suggested the emergence of artemisinin resistance. Vietnam shares a long land border with Cambodia with a large number of migrants crossing it on a daily basis. Therefore, there is an urgent need to investigate whether there is any evidence of a change in the parasitological response to the artemisinin derivatives in Vietnam.
From August 2010 to May 2011, a randomized controlled clinical trial in uncomplicated falciparum malaria was conducted to compare two doses of artesunate (AS) (2mg/kg/day versus 4 mg/kg/day for three days) followed by dihydroartemisinin-piperaquine (DHA-PPQ) and a control arm of DHA-PPQ. The goal was characterization of the current efficacy of artesunate in southern Vietnam. The primary endpoint of this study was the parasite clearance half-life; secondary endpoints included the parasite reduction ratios at 24 and 48 hours and the parasite clearance time.
166 patients were recruited into the study. The median parasite clearance half-lives were 3.54 (AS 2mg/kg), 2.72 (AS 4mg/kg), and 2.98 hours (DHA-PPQ) (p=0.19). The median parasite-reduction ratio at 24 hours was 48 in the AS 2mg/kg group compared with 212 and 113 in the other two groups, respectively (p=0.02). The proportions of patients with a parasite clearance time of >72 hours for AS 2mg/kg, AS 4mg/kg and DHA-PPQ were 27%, 27%, and 22%, respectively. Early treatment failure occurred in two (4%) and late clinical failure occurred in one (2%) of the 55 patients in the AS 2mg/kg group, as compared with none in the other two study arms. The PCR-corrected adequate clinical and parasitological response (APCR) rates in the three groups were 94%, 100%, and 100% (p=0.04).
This study demonstrated faster P. falciparum parasite clearance in southern Vietnam than in western Cambodia but slower clearance in comparison with historical data from Vietnam. Further studies to determine whether this represents the emergence of artemisinin resistance in this area are needed. Currently, the therapeutic response to DHA-PPQ remains satisfactory in southern Vietnam.
NTC01165372.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Fatal consequences of freshwater pearl diving Phu, Nguyen Hoan, MD; Hoang Mai, Nguyen Thi, MD; Nghia, Ho Dang Trung, MD ...
The Lancet (British edition),
01/2013, Letnik:
381, Številka:
9861
Journal Article
Recenzirano
Odprti dostop
Polymerase chain reaction (PCR) amplification targeting the 18s RNA gene was done retrospectively.1 The PCR amplicon was sequenced and confirmed to have 100% homology with the 18s RNA gene of ...Naegleria fowleri, which is the cause of primary amoebic meningoencephalitis. Within the central nervous system N fowleri amoebae cause an intense inflammatory reaction accompanied by necrosis and haemorrhage.3 Amoebic meningoencephalitis seems to be increasing in frequency with an expanding geographic footprint.4,5 Clinical and CSF findings are difficult to distinguish from bacterial meningitis.5 A history of freshwater exposure and symptoms such as the loss of the sense of smell should prompt consideration of the disease.4 The infection has a very high case-fatality rate and very few survivors have been documented.
Summary
In order to obtain an approximate assessment of the public health burden that will be posed by the inherited disorders of haemoglobin in southern Vietnam, several thousand individuals were ...screened for these conditions. A smaller sample was screened for glucose‐6‐phosphate dehydrogenase (G6PD) deficiency. The important haemoglobin disorders identified were β thalassaemia, haemoglobin E and a variety of different forms of α thalassaemia. There were sufficient G6PD‐deficient individuals to materially affect malaria control programme design. The most remarkable finding was wide variation in the gene frequencies of these conditions among the ethnic groups sampled. The approximate number of babies expected to be born with clinically significant haemoglobin disorders in Vietnam was estimated from the gene‐frequency data. This study emphasizes the importance of wide‐scale population screening, including ethnic subgroups, to establish the requirements for inherited haemoglobin disorder programmes in resource‐limited settings.
A total of 128 Vietnamese patients with symptomatic Plasmodium vivax mono-infections were enrolled in a prospective, open-label, randomized trial to receive either chloroquine or ...dihydroartemisinin-piperaquine (DHA-PPQ). The proportions of patients with adequate clinical and parasitological responses were 47% in the chloroquine arm (31 of 65 patients) and 66% in the DHA-PPQ arm (42 of 63 patients) in the Kaplan-Meier intention-to-treat analysis (absolute difference 19%, 95% confidence interval = 0-37%), thus establishing non-inferiority of DHA-PPQ. Fever clearance time (median 24 versus 12 hours,P= 0.02), parasite clearance time (median 36 versus 18 hours,P< 0.001), and parasite clearance half-life (mean 3.98 versus 1.80 hours,P< 0.001) were all significantly shorter in the DHA-PPQ arm. All cases of recurrent parasitemia in the chloroquine arm occurred from day 33 onward, with corresponding whole blood chloroquine concentration lower than 100 ng/mL in all patients. Chloroquine thus remains efficacious for the treatment of P. vivax malaria in southern Vietnam, but DHA-PPQ provides more rapid symptomatic and parasitological recovery.
Many human genetic associations with resistance to malaria have been reported but few have been reliably replicated. We collected data on 11,890 cases of severe malaria due to
Plasmodium falciparum
...and 17,441 controls from 12 locations in Africa, Asia and Oceania. There was strong evidence of association with the
HBB, ABO, ATP2B4, G6PD
and
CD40LG
loci but previously reported associations at 22 other loci did not replicate in the multi-centre analysis. The large sample size made it possible to identify authentic genetic effects that are heterogeneous across populations or phenotypes, a striking example being the main African form of G6PD deficiency, which reduced the risk of cerebral malaria but increased the risk of severe malarial anaemia. The finding that G6PD deficiency has opposing effects on different fatal complications of
P. falciparum
infection indicates that the evolutionary origins of this common human genetic disorder are more complex than previously supposed.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Streptococcus suis infection, an emerging zoonosis, is an increasing public health problem across South East Asia and the most common cause of acute bacterial meningitis in adults in Vietnam. Little ...is known of the risk factors underlying the disease.
A case-control study with appropriate hospital and matched community controls for each patient was conducted between May 2006 and June 2009. Potential risk factors were assessed using a standardized questionnaire and investigation of throat and rectal S. suis carriage in cases, controls and their pigs, using real-time PCR and culture of swab samples. We recruited 101 cases of S. suis meningitis, 303 hospital controls and 300 community controls. By multivariate analysis, risk factors identified for S. suis infection as compared to either control group included eating "high risk" dishes, including such dishes as undercooked pig blood and pig intestine (OR(1) = 2.22; 95%CI = 1.15-4.28 and OR(2) = 4.44; 95%CI = 2.15-9.15), occupations related to pigs (OR(1) = 3.84; 95%CI = 1.32-11.11 and OR(2) = 5.52; 95%CI = 1.49-20.39), and exposures to pigs or pork in the presence of skin injuries (OR(1) = 7.48; 95%CI = 1.97-28.44 and OR(2) = 15.96; 95%CI = 2.97-85.72). S. suis specific DNA was detected in rectal and throat swabs of 6 patients and was cultured from 2 rectal samples, but was not detected in such samples of 1522 healthy individuals or patients without S. suis infection.
This case control study, the largest prospective epidemiological assessment of this disease, has identified the most important risk factors associated with S. suis bacterial meningitis to be eating 'high risk' dishes popular in parts of Asia, occupational exposure to pigs and pig products, and preparation of pork in the presence of skin lesions. These risk factors can be addressed in public health campaigns aimed at preventing S. suis infection.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The genetic basis for susceptibility to malaria has been studied widely in African populations but less is known of the contribution of specific genetic variants in Asian populations. We genotyped 67 ...SNPs in 1030 severe malaria cases and 2840 controls from Vietnam. After data quality control, genotyping data of 956 cases and 2350 controls were analysed for 65 SNPs (3 gender confirmation, 62 positioned in/near 42 malarial candidate genes). 14 SNPs were monomorphic and 2 (rs8078340 and rs33950507) were not in HWE in controls (
P
<0.01). 7/46 SNPs in 6 genes (ICAM1, IL1A, IL17RC, IL13, LTA and TNF) were associated with severe malaria, with 3/7 SNPs in the TNFA/LTA region . Genotype phenotype correlations between SNPs and clinical parameters revealed that genotypes of rs708567 (IL17RC) correlate with parasitemia (
P
=0.028, r
2
=0.0086), with GG homozygotes having the lowest parasite burden. Additionally, rs708567 GG homozygotes had a decreased risk of severe malaria
P
=0.007, OR=0.78 (95% CI; 0.65-0.93) and death
P
=0.028, OR=0.58 (95% CI; 0.37-0.93) than those with AA and AG genotypes. In summary, variants in 6 genes encoding adhesion and pro-inflammatory molecules are associated with severe malaria in the Vietnamese. Further replicative studies in independent populations will be necessary to confirm these findings.
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