Media Releases

Food insecurity leads to increased incidence of tuberculosis in Zimbabwe

February 5, 2014

TORONTO, ON — The rise of tuber­cu­lo­sis (TB) in Zim­bab­we dur­ing the socio-eco­nom­ic cri­sis of 2008–9 has been linked to wide­spread food short­age, accord­ing to a new study led by Cana­di­an researchers from the Uni­ver­si­ty of Toron­to Dal­la Lana School of Pub­lic Health pub­lished in PLOS ONE.

“This was the first study to detect the recent TB out­break in Zim­bab­we, and the first any­where to sug­gest an asso­ci­a­tion between ris­ing TB inci­dence and nation­al eco­nom­ic decline in the absence of armed con­flict,” said Michael Sil­ver­man, assis­tant pro­fes­sor at the Dal­la Lana School of Pub­lic Health and senior author of the study. Although the same phe­nom­e­non may occur with oth­er infec­tious dis­eases, the study focused on TB – one of the largest caus­es of mor­bid­i­ty and mor­tal­i­ty in Zim­bab­we, espe­cial­ly among peo­ple liv­ing with HIV.

“Zim­bab­we may have been pre­dis­posed to this TB out­break due to the pres­ence of a large HIV-pos­i­tive pop­u­la­tion who were par­tic­u­lar­ly vul­ner­a­ble to the effects of food short­ages which led to mal­nu­tri­tion and fur­ther dam­age to already weak­ened immune sys­tems,” said Sil­ver­man.

Many devel­op­ing coun­tries have large HIV pos­i­tive pop­u­la­tions and thus socioe­co­nom­ic insta­bil­i­ty could lead to a sim­i­lar prob­lem else­where. “This find­ing empha­sizes the impor­tance of ade­quate food avail­abil­i­ty in con­trol­ling TB inci­dence, par­tic­u­lar­ly in areas with high HIV preva­lence,” said Sil­ver­man.

The study also demon­strat­ed that TB inci­dence appears to be sea­son­al, with a larg­er num­ber of cas­es when food is scarce in the dry sea­son and low­er num­bers of cas­es post-har­vest when food is more plen­ti­ful. Research data also sug­gests that TB inci­dence fell back to pre-cri­sis lev­els when the econ­o­my of the coun­try and food secu­ri­ty improved after 2009.

“Polit­i­cal insta­bil­i­ty can lead to eco­nom­ic insta­bil­i­ty, and this can lead to a health cri­sis with the most vul­ner­a­ble peo­ple in soci­ety the most like­ly to be harmed,” said Sil­ver­man. “It is impor­tant for polit­i­cal lead­ers to be aware that in addi­tion to eco­nom­ic costs, polit­i­cal con­flict can poten­tial­ly have very seri­ous health impli­ca­tions for vul­ner­a­ble com­mu­ni­ties.”

This study was co-authored by Stephen Burke of the Uni­ver­si­ty of Ottawa and Elliot Lass of the Uni­ver­si­ty of Toron­to; Paul This­tle of U of T and the Uni­ver­si­ty of Zim­bab­we; Arif Jetha, Shelly Bolotin and Andrew Simor of the Dal­la Lana School of Pub­lic Health; Love­more Katumbe of the Howard Hos­pi­tal in Zim­bab­we; Dan Schwarz of Brigham and Women’s Hos­pi­tal and Children’s Hos­pi­tal of Boston; and Jack Bark­er of the Mura­bin­da Mis­sion Hos­pi­tal in Zim­bab­we and King’s Col­lege Hos­pi­tal in the UK.


For more infor­ma­tion, con­tact:

Michael Sil­ver­man MD, FRCP
Assis­tant Pro­fes­sor
Uni­ver­si­ty of Toron­to, Dal­la Lana School of Pub­lic Health
Tel: 416–877-7641

Jele­na Dam­janovic
Media Assis­tant
Uni­ver­si­ty of Toron­to