This site needs JavaScript to work properly. Please enable it to take advantage of the complete set of features!
Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

NIH NLM Logo
Log in
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2012;6(5):e1621.
doi: 10.1371/journal.pntd.0001621. Epub 2012 May 8.

Soil-transmitted helminth reinfection after drug treatment: a systematic review and meta-analysis

Affiliations
Meta-Analysis

Soil-transmitted helminth reinfection after drug treatment: a systematic review and meta-analysis

Tie-Wu Jia et al. PLoS Negl Trop Dis. 2012.

Abstract

Background: Soil-transmitted helminth (STH) infections (i.e., Ascaris lumbricoides, hookworm, and Trichuris trichiura) affect more than a billion people. Preventive chemotherapy (i.e., repeated administration of anthelmintic drugs to at-risk populations), is the mainstay of control. This strategy, however, does not prevent reinfection. We performed a systematic review and meta-analysis to assess patterns and dynamics of STH reinfection after drug treatment.

Methodology: We systematically searched PubMed, ISI Web of Science, EMBASE, Cochrane Database of Systematic Reviews, China National Knowledge Infrastructure, WanFang Database, Chinese Scientific Journal Database, and Google Scholar. Information on study year, country, sample size, age of participants, diagnostic method, drug administration strategy, prevalence and intensity of infection pre- and posttreatment, cure and egg reduction rate, evaluation period posttreatment, and adherence was extracted. Pooled risk ratios from random-effects models were used to assess the risk of STH reinfection after treatment. Our protocol is available on PROSPERO, registration number: CRD42011001678.

Principal findings: From 154 studies identified, 51 were included and 24 provided STH infection rates pre- and posttreatment, whereas 42 reported determinants of predisposition to reinfection. At 3, 6, and 12 months posttreatment, A. lumbricoides prevalence reached 26% (95% confidence interval (CI): 16-43%), 68% (95% CI: 60-76%) and 94% (95% CI: 88-100%) of pretreatment levels, respectively. For T. trichiura, respective reinfection prevalence were 36% (95% CI: 28-47%), 67% (95% CI: 42-100%), and 82% (95% CI: 62-100%), and for hookworm, 30% (95% CI: 26-34%), 55% (95% CI: 34-87%), and 57% (95% CI: 49-67%). Prevalence and intensity of reinfection were positively correlated with pretreatment infection status.

Conclusion: STH reinfections occur rapidly after treatment, particularly for A. lumbricoides and T. trichiura. Hence, there is a need for frequent anthelmintic drug administrations to maximize the benefit of preventive chemotherapy. Integrated control approaches emphasizing health education and environmental sanitation are needed to interrupt transmission of STH.

PubMed Disclaimer

Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Flowchart visualizing the procedure for identifying relevant publications.
aThe original article or full text could not be obtained. b14 parasitology: 9 dynamics and structure of population, 4 immunology, 1 quantitative measure method of reinfection. cExtended analysis of previously published study. d2 on enteroparasite (intestinal parasites including Enterobius vermicularis, Hymenolepis nana, Giardia intestinalis, Entamoeba coli, Entamoeba histolytica, and others), 1 on bancroftian filariasis.
Figure 2
Figure 2. Forest plot of prevalence of Ascaris lumbricoides 3, 6, and 12 months posttreatment.
A random relative risk (RR) value of less than 1 indicates a lower infection rate after treatment compared to the initial level. Diamonds represent the pooled estimate across studies. See Table S1 for full references. *The infection rate 3 or 6 months after the last round of treatment was abstracted (Table S3).
Figure 3
Figure 3. Forest plot of prevalence of Trichuris trichiura or hookworm after treatment.
A random relative risk (RR) value of less than 1 indicates a lower infection rate after treatment compared to the initial level. Diamonds represent the pooled estimate across studies. See Table S1 for full references. *The infection rate 6 months after the last round of treatment was abstracted (Table S3).
Figure 4
Figure 4. Summary of the rapidity of re-acquiring soil-transmitted helminth (STH) infections after treatment.

References

    1. Hotez PJ, Molyneux DH, Fenwick A, Kumaresan J, Sachs SE, et al. Control of neglected tropical diseases. N Engl J Med. 2007;357:1018–1027. - PubMed
    1. Hotez PJ, Brindley PJ, Bethony JM, King CH, Pearce EJ, et al. Helminth infections: the great neglected tropical diseases. J Clin Invest. 2008;118:1311–1321. - PMC - PubMed
    1. de Silva NR, Brooker S, Hotez PJ, Montresor A, Engels D, et al. Soil-transmitted helminth infections: updating the global picture. Trends Parasitol. 2003;19:547–551. - PubMed
    1. Vandemark LM, Jia TW, Zhou XN. Social science implications for control of helminth infections in Southeast Asia. Adv Parasitol. 2010;73:137–170. - PubMed
    1. Alemu A, Atnafu A, Addis Z, Shiferaw Y, Teklu T, et al. Soil transmitted helminths and schistosoma mansoni infections among school children in Zarima town, northwest Ethiopia. BMC Infect Dis. 2011;11:189. - PMC - PubMed

Publication types

Full text links
Public Library of Science full text link Public Library of Science Free PMC article
Cite

AltStyle によって変換されたページ (->オリジナル) /