Ascaris lumbricoides infection and its relation to environmental factors in the Mbeya region of Tanzania, a cross-sectional, population-based study.
BACKGROUND: With one quarter of the world population infected, the intestinal nematode Ascaris lumbricoides is one of the most common infectious agents, especially in the tropics and sub-tropics. Infection is caused by oral intake of eggs and can cause respiratory and gastrointestinal problems. To i...
| Main Authors: | , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2014-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC3958400?pdf=render |
| _version_ | 1811320830176526336 |
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| author | Steffen Andreas Schüle Petra Clowes Inge Kroidl Dickens O Kowuor Anthony Nsojo Chacha Mangu Helene Riess Christof Geldmacher Rüdiger Paul Laubender Seif Mhina Leonard Maboko Thomas Löscher Michael Hoelscher Elmar Saathoff |
| author_facet | Steffen Andreas Schüle Petra Clowes Inge Kroidl Dickens O Kowuor Anthony Nsojo Chacha Mangu Helene Riess Christof Geldmacher Rüdiger Paul Laubender Seif Mhina Leonard Maboko Thomas Löscher Michael Hoelscher Elmar Saathoff |
| author_sort | Steffen Andreas Schüle |
| collection | DOAJ |
| description | BACKGROUND: With one quarter of the world population infected, the intestinal nematode Ascaris lumbricoides is one of the most common infectious agents, especially in the tropics and sub-tropics. Infection is caused by oral intake of eggs and can cause respiratory and gastrointestinal problems. To identify high risk areas for intervention, it is necessary to understand the effects of climatic, environmental and socio-demographic conditions on A. lumbricoides infection. METHODOLOGY: Cross-sectional survey data of 6,366 study participants in the Mbeya region of South-Western Tanzania were used to analyze associations between remotely sensed environmental data and A. lumbricoides infection. Non-linear associations were accounted for by using fractional polynomial regression, and socio-demographic and sanitary data were included as potential confounders. PRINCIPAL FINDINGS: The overall prevalence of A. lumbricoides infection was 6.8%. Our final multivariable model revealed a significant non-linear association between rainfall and A. lumbricoides infection with peak prevalences at 1740 mm of mean annual rainfall. Mean annual land surface temperature during the day was linearly modeled and negatively associated with A. lumbricoides infection (odds ratio (OR) = 0.87, 95% confidence interval (CI) = 0.78-0.97). Furthermore, age, which also showed a significant non-linear association (infection maximum at 7.7 years), socio-economic status (OR = 0.82, CI = 0.68-0.97), and latrine coverage around the house (OR = 0.80, CI = 0.67-0.96) remained in the final model. CONCLUSIONS: A. lumbricoides infection was associated with environmental, socio-demographic and sanitary factors both in uni- and multivariable analysis. Non-linear analysis with fractional polynomials can improve model fit, resulting in a better understanding of the relationship between environmental conditions and helminth infection, and more precise predictions of high prevalence areas. However, socio-demographic determinants and sanitary conditions should also be considered, especially when planning public health interventions on a smaller scale, such as the community level. |
| first_indexed | 2024-04-13T13:07:34Z |
| format | Article |
| id | doaj.art-8faf9ea109ec4cf68d25b573ef2af394 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-04-13T13:07:34Z |
| publishDate | 2014-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-8faf9ea109ec4cf68d25b573ef2af3942022-12-22T02:45:44ZengPublic Library of Science (PLoS)PLoS ONE1932-62032014-01-0193e9203210.1371/journal.pone.0092032Ascaris lumbricoides infection and its relation to environmental factors in the Mbeya region of Tanzania, a cross-sectional, population-based study.Steffen Andreas SchülePetra ClowesInge KroidlDickens O KowuorAnthony NsojoChacha ManguHelene RiessChristof GeldmacherRüdiger Paul LaubenderSeif MhinaLeonard MabokoThomas LöscherMichael HoelscherElmar SaathoffBACKGROUND: With one quarter of the world population infected, the intestinal nematode Ascaris lumbricoides is one of the most common infectious agents, especially in the tropics and sub-tropics. Infection is caused by oral intake of eggs and can cause respiratory and gastrointestinal problems. To identify high risk areas for intervention, it is necessary to understand the effects of climatic, environmental and socio-demographic conditions on A. lumbricoides infection. METHODOLOGY: Cross-sectional survey data of 6,366 study participants in the Mbeya region of South-Western Tanzania were used to analyze associations between remotely sensed environmental data and A. lumbricoides infection. Non-linear associations were accounted for by using fractional polynomial regression, and socio-demographic and sanitary data were included as potential confounders. PRINCIPAL FINDINGS: The overall prevalence of A. lumbricoides infection was 6.8%. Our final multivariable model revealed a significant non-linear association between rainfall and A. lumbricoides infection with peak prevalences at 1740 mm of mean annual rainfall. Mean annual land surface temperature during the day was linearly modeled and negatively associated with A. lumbricoides infection (odds ratio (OR) = 0.87, 95% confidence interval (CI) = 0.78-0.97). Furthermore, age, which also showed a significant non-linear association (infection maximum at 7.7 years), socio-economic status (OR = 0.82, CI = 0.68-0.97), and latrine coverage around the house (OR = 0.80, CI = 0.67-0.96) remained in the final model. CONCLUSIONS: A. lumbricoides infection was associated with environmental, socio-demographic and sanitary factors both in uni- and multivariable analysis. Non-linear analysis with fractional polynomials can improve model fit, resulting in a better understanding of the relationship between environmental conditions and helminth infection, and more precise predictions of high prevalence areas. However, socio-demographic determinants and sanitary conditions should also be considered, especially when planning public health interventions on a smaller scale, such as the community level.http://europepmc.org/articles/PMC3958400?pdf=render |
| spellingShingle | Steffen Andreas Schüle Petra Clowes Inge Kroidl Dickens O Kowuor Anthony Nsojo Chacha Mangu Helene Riess Christof Geldmacher Rüdiger Paul Laubender Seif Mhina Leonard Maboko Thomas Löscher Michael Hoelscher Elmar Saathoff Ascaris lumbricoides infection and its relation to environmental factors in the Mbeya region of Tanzania, a cross-sectional, population-based study. PLoS ONE |
| title | Ascaris lumbricoides infection and its relation to environmental factors in the Mbeya region of Tanzania, a cross-sectional, population-based study. |
| title_full | Ascaris lumbricoides infection and its relation to environmental factors in the Mbeya region of Tanzania, a cross-sectional, population-based study. |
| title_fullStr | Ascaris lumbricoides infection and its relation to environmental factors in the Mbeya region of Tanzania, a cross-sectional, population-based study. |
| title_full_unstemmed | Ascaris lumbricoides infection and its relation to environmental factors in the Mbeya region of Tanzania, a cross-sectional, population-based study. |
| title_short | Ascaris lumbricoides infection and its relation to environmental factors in the Mbeya region of Tanzania, a cross-sectional, population-based study. |
| title_sort | ascaris lumbricoides infection and its relation to environmental factors in the mbeya region of tanzania a cross sectional population based study |
| url | http://europepmc.org/articles/PMC3958400?pdf=render |
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