Changing epidemiology of malaria in Sabah, Malaysia

Increasing incidence of Plasmodium knowlesi

Timothy Williams, Jenarun Jelip, Jayaram Menon, F Anderios, Rashidah Mohammad, Tajul Mohammad, Matthew Grigg, Tsin Yeo, Nicholas Anstey, Bridget Barber

    Research output: Contribution to journalArticleResearchpeer-review

    7 Downloads (Pure)

    Abstract

    Background: While Malaysia has had great success in controlling Plasmodium falciparum and Plasmodium vivax, notifications of Plasmodium malariae and the microscopically near-identical Plasmodium knowlesi increased substantially over the past decade. However, whether this represents microscopic misdiagnosis or increased recognition of P. knowlesi has remained uncertain.

    Methods: To describe the changing epidemiology of malaria in Sabah, in particular the increasing incidence of P. knowlesi, a retrospective descriptive study was undertaken involving a review of Department of Health malaria notification data from 2012–2013, extending a previous review of these data from 1992–2011. In addition, malaria PCR and microscopy data from the State Public Health Laboratory were reviewed to estimate the accuracy of the microscopy-based notification data.

    Results: Notifications of P. malariae/P. knowlesi increased from 703 in 2011 to 815 in 2012 and 996 in 2013. Notifications of P. vivax and P. falciparum decreased from 605 and 628, respectively, in 2011, to 297 and 263 in 2013. In 2013, P. malariae/P. knowlesi accounted for 62% of all malaria notifications compared to 35% in 2011. Among 1,082 P. malariae/P. knowlesi blood slides referred for PCR testing during 2011–2013, there were 924 (85%) P. knowlesi mono-infections, 30 (2.8%) P. falciparum, 43 (4.0%) P. vivax, seven (0.6%) P. malariae, six (0.6%) mixed infections, 31 (2.9%) positive only for Plasmodium genus, and 41 (3.8%) Plasmodium-negative. Plasmodium knowlesi mono-infection accounted for 32/156 (21%) and 33/87 (38%) blood slides diagnosed by microscopy as P. falciparum and P. vivax, respectively. Twenty-six malaria deaths were reported during 2010–2013, including 12 with ‘P. malariae/P. knowlesi’ (all adults), 12 with P. falciparum (seven adults), and two adults with P. vivax.

    Conclusions: Notifications of P. malariae/P. knowlesi in Sabah are increasing, with this trend likely reflecting a true increase in incidence of P. knowlesi and presenting a major threat to malaria control and elimination in Malaysia. With the decline of P. falciparum and P. vivax, control programmes need to incorporate measures to protect against P. knowlesi, with further research required to determine effective interventions.
    Original languageEnglish
    Article number390
    Pages (from-to)1-11
    Number of pages11
    JournalMalaria Journal
    Volume13
    Issue number390
    DOIs
    Publication statusPublished - 2014

    Fingerprint

    Plasmodium knowlesi
    Malaysia
    Malaria
    Plasmodium malariae
    Epidemiology
    Plasmodium vivax
    Plasmodium falciparum
    Incidence
    Microscopy
    Plasmodium
    Polymerase Chain Reaction
    Diagnostic Errors
    Coinfection
    Retrospective Studies
    Public Health

    Cite this

    Williams, Timothy ; Jelip, Jenarun ; Menon, Jayaram ; Anderios, F ; Mohammad, Rashidah ; Mohammad, Tajul ; Grigg, Matthew ; Yeo, Tsin ; Anstey, Nicholas ; Barber, Bridget. / Changing epidemiology of malaria in Sabah, Malaysia : Increasing incidence of Plasmodium knowlesi. In: Malaria Journal. 2014 ; Vol. 13, No. 390. pp. 1-11.
    @article{6c626752ee9f4e97bb0b783ef4af4819,
    title = "Changing epidemiology of malaria in Sabah, Malaysia: Increasing incidence of Plasmodium knowlesi",
    abstract = "Background: While Malaysia has had great success in controlling Plasmodium falciparum and Plasmodium vivax, notifications of Plasmodium malariae and the microscopically near-identical Plasmodium knowlesi increased substantially over the past decade. However, whether this represents microscopic misdiagnosis or increased recognition of P. knowlesi has remained uncertain.Methods: To describe the changing epidemiology of malaria in Sabah, in particular the increasing incidence of P. knowlesi, a retrospective descriptive study was undertaken involving a review of Department of Health malaria notification data from 2012–2013, extending a previous review of these data from 1992–2011. In addition, malaria PCR and microscopy data from the State Public Health Laboratory were reviewed to estimate the accuracy of the microscopy-based notification data.Results: Notifications of P. malariae/P. knowlesi increased from 703 in 2011 to 815 in 2012 and 996 in 2013. Notifications of P. vivax and P. falciparum decreased from 605 and 628, respectively, in 2011, to 297 and 263 in 2013. In 2013, P. malariae/P. knowlesi accounted for 62{\%} of all malaria notifications compared to 35{\%} in 2011. Among 1,082 P. malariae/P. knowlesi blood slides referred for PCR testing during 2011–2013, there were 924 (85{\%}) P. knowlesi mono-infections, 30 (2.8{\%}) P. falciparum, 43 (4.0{\%}) P. vivax, seven (0.6{\%}) P. malariae, six (0.6{\%}) mixed infections, 31 (2.9{\%}) positive only for Plasmodium genus, and 41 (3.8{\%}) Plasmodium-negative. Plasmodium knowlesi mono-infection accounted for 32/156 (21{\%}) and 33/87 (38{\%}) blood slides diagnosed by microscopy as P. falciparum and P. vivax, respectively. Twenty-six malaria deaths were reported during 2010–2013, including 12 with ‘P. malariae/P. knowlesi’ (all adults), 12 with P. falciparum (seven adults), and two adults with P. vivax.Conclusions: Notifications of P. malariae/P. knowlesi in Sabah are increasing, with this trend likely reflecting a true increase in incidence of P. knowlesi and presenting a major threat to malaria control and elimination in Malaysia. With the decline of P. falciparum and P. vivax, control programmes need to incorporate measures to protect against P. knowlesi, with further research required to determine effective interventions.",
    keywords = "rain, adult, age, Article, death, female, geographic distribution, human, major clinical study, Malaysia, male, microscopy, morbidity, Plasmodium falciparum, Plasmodium knowlesi, Plasmodium knowlesi malaria, Plasmodium malariae, Plasmodium vivax, polymerase chain reaction, sex ratio, adolescent, aged, child, genetics, incidence, infant, isolation and purification, malaria, middle aged, newborn, parasitology, preschool child, retrospective study, season, very elderly, young adult, Adolescent, Adult, Aged, Aged, 80 and over, Child, Child, Preschool, Female, Humans, Incidence, Infant, Infant, Newborn, Malaria, Male, Middle Aged, Polymerase Chain Reaction, Retrospective Studies, Seasons, Young Adult",
    author = "Timothy Williams and Jenarun Jelip and Jayaram Menon and F Anderios and Rashidah Mohammad and Tajul Mohammad and Matthew Grigg and Tsin Yeo and Nicholas Anstey and Bridget Barber",
    year = "2014",
    doi = "10.1186/1475-2875-13-390",
    language = "English",
    volume = "13",
    pages = "1--11",
    journal = "Malaria Journal",
    issn = "1475-2875",
    publisher = "BioMed Central",
    number = "390",

    }

    Williams, T, Jelip, J, Menon, J, Anderios, F, Mohammad, R, Mohammad, T, Grigg, M, Yeo, T, Anstey, N & Barber, B 2014, 'Changing epidemiology of malaria in Sabah, Malaysia: Increasing incidence of Plasmodium knowlesi', Malaria Journal, vol. 13, no. 390, 390, pp. 1-11. https://doi.org/10.1186/1475-2875-13-390

    Changing epidemiology of malaria in Sabah, Malaysia : Increasing incidence of Plasmodium knowlesi. / Williams, Timothy; Jelip, Jenarun; Menon, Jayaram; Anderios, F; Mohammad, Rashidah; Mohammad, Tajul; Grigg, Matthew; Yeo, Tsin; Anstey, Nicholas; Barber, Bridget.

    In: Malaria Journal, Vol. 13, No. 390, 390, 2014, p. 1-11.

    Research output: Contribution to journalArticleResearchpeer-review

    TY - JOUR

    T1 - Changing epidemiology of malaria in Sabah, Malaysia

    T2 - Increasing incidence of Plasmodium knowlesi

    AU - Williams, Timothy

    AU - Jelip, Jenarun

    AU - Menon, Jayaram

    AU - Anderios, F

    AU - Mohammad, Rashidah

    AU - Mohammad, Tajul

    AU - Grigg, Matthew

    AU - Yeo, Tsin

    AU - Anstey, Nicholas

    AU - Barber, Bridget

    PY - 2014

    Y1 - 2014

    N2 - Background: While Malaysia has had great success in controlling Plasmodium falciparum and Plasmodium vivax, notifications of Plasmodium malariae and the microscopically near-identical Plasmodium knowlesi increased substantially over the past decade. However, whether this represents microscopic misdiagnosis or increased recognition of P. knowlesi has remained uncertain.Methods: To describe the changing epidemiology of malaria in Sabah, in particular the increasing incidence of P. knowlesi, a retrospective descriptive study was undertaken involving a review of Department of Health malaria notification data from 2012–2013, extending a previous review of these data from 1992–2011. In addition, malaria PCR and microscopy data from the State Public Health Laboratory were reviewed to estimate the accuracy of the microscopy-based notification data.Results: Notifications of P. malariae/P. knowlesi increased from 703 in 2011 to 815 in 2012 and 996 in 2013. Notifications of P. vivax and P. falciparum decreased from 605 and 628, respectively, in 2011, to 297 and 263 in 2013. In 2013, P. malariae/P. knowlesi accounted for 62% of all malaria notifications compared to 35% in 2011. Among 1,082 P. malariae/P. knowlesi blood slides referred for PCR testing during 2011–2013, there were 924 (85%) P. knowlesi mono-infections, 30 (2.8%) P. falciparum, 43 (4.0%) P. vivax, seven (0.6%) P. malariae, six (0.6%) mixed infections, 31 (2.9%) positive only for Plasmodium genus, and 41 (3.8%) Plasmodium-negative. Plasmodium knowlesi mono-infection accounted for 32/156 (21%) and 33/87 (38%) blood slides diagnosed by microscopy as P. falciparum and P. vivax, respectively. Twenty-six malaria deaths were reported during 2010–2013, including 12 with ‘P. malariae/P. knowlesi’ (all adults), 12 with P. falciparum (seven adults), and two adults with P. vivax.Conclusions: Notifications of P. malariae/P. knowlesi in Sabah are increasing, with this trend likely reflecting a true increase in incidence of P. knowlesi and presenting a major threat to malaria control and elimination in Malaysia. With the decline of P. falciparum and P. vivax, control programmes need to incorporate measures to protect against P. knowlesi, with further research required to determine effective interventions.

    AB - Background: While Malaysia has had great success in controlling Plasmodium falciparum and Plasmodium vivax, notifications of Plasmodium malariae and the microscopically near-identical Plasmodium knowlesi increased substantially over the past decade. However, whether this represents microscopic misdiagnosis or increased recognition of P. knowlesi has remained uncertain.Methods: To describe the changing epidemiology of malaria in Sabah, in particular the increasing incidence of P. knowlesi, a retrospective descriptive study was undertaken involving a review of Department of Health malaria notification data from 2012–2013, extending a previous review of these data from 1992–2011. In addition, malaria PCR and microscopy data from the State Public Health Laboratory were reviewed to estimate the accuracy of the microscopy-based notification data.Results: Notifications of P. malariae/P. knowlesi increased from 703 in 2011 to 815 in 2012 and 996 in 2013. Notifications of P. vivax and P. falciparum decreased from 605 and 628, respectively, in 2011, to 297 and 263 in 2013. In 2013, P. malariae/P. knowlesi accounted for 62% of all malaria notifications compared to 35% in 2011. Among 1,082 P. malariae/P. knowlesi blood slides referred for PCR testing during 2011–2013, there were 924 (85%) P. knowlesi mono-infections, 30 (2.8%) P. falciparum, 43 (4.0%) P. vivax, seven (0.6%) P. malariae, six (0.6%) mixed infections, 31 (2.9%) positive only for Plasmodium genus, and 41 (3.8%) Plasmodium-negative. Plasmodium knowlesi mono-infection accounted for 32/156 (21%) and 33/87 (38%) blood slides diagnosed by microscopy as P. falciparum and P. vivax, respectively. Twenty-six malaria deaths were reported during 2010–2013, including 12 with ‘P. malariae/P. knowlesi’ (all adults), 12 with P. falciparum (seven adults), and two adults with P. vivax.Conclusions: Notifications of P. malariae/P. knowlesi in Sabah are increasing, with this trend likely reflecting a true increase in incidence of P. knowlesi and presenting a major threat to malaria control and elimination in Malaysia. With the decline of P. falciparum and P. vivax, control programmes need to incorporate measures to protect against P. knowlesi, with further research required to determine effective interventions.

    KW - rain

    KW - adult

    KW - age

    KW - Article

    KW - death

    KW - female

    KW - geographic distribution

    KW - human

    KW - major clinical study

    KW - Malaysia

    KW - male

    KW - microscopy

    KW - morbidity

    KW - Plasmodium falciparum

    KW - Plasmodium knowlesi

    KW - Plasmodium knowlesi malaria

    KW - Plasmodium malariae

    KW - Plasmodium vivax

    KW - polymerase chain reaction

    KW - sex ratio

    KW - adolescent

    KW - aged

    KW - child

    KW - genetics

    KW - incidence

    KW - infant

    KW - isolation and purification

    KW - malaria

    KW - middle aged

    KW - newborn

    KW - parasitology

    KW - preschool child

    KW - retrospective study

    KW - season

    KW - very elderly

    KW - young adult

    KW - Adolescent

    KW - Adult

    KW - Aged

    KW - Aged, 80 and over

    KW - Child

    KW - Child, Preschool

    KW - Female

    KW - Humans

    KW - Incidence

    KW - Infant

    KW - Infant, Newborn

    KW - Malaria

    KW - Male

    KW - Middle Aged

    KW - Polymerase Chain Reaction

    KW - Retrospective Studies

    KW - Seasons

    KW - Young Adult

    UR - http://www.scopus.com/inward/record.url?scp=84908092609&partnerID=8YFLogxK

    U2 - 10.1186/1475-2875-13-390

    DO - 10.1186/1475-2875-13-390

    M3 - Article

    VL - 13

    SP - 1

    EP - 11

    JO - Malaria Journal

    JF - Malaria Journal

    SN - 1475-2875

    IS - 390

    M1 - 390

    ER -