Photographs by Esther Ruth Mbabazi March 2022, ScientificAmerican.com 41A
decade ago Willy SSengooba began criSScroSSing Uganda, training health-care
workers on how to use a new machine to detect tuberculosis. The deadly lung
disease infects around 90,000 people in the East African nation annually, but
it can sometimes take months to diagnose using traditional methods such as
culturing samples of coughed-up sputum. These new machines used rapid
molecular testing to yield results within a couple of hours, meaning patients
who tested positive could immediately be referred for lifesaving treatment. Ssen-
gooba, who is scientific director of the mycobacteriology research unit at the Makerere Univer-
sity College of Health Sciences in Kampala, helped to set up 265 of the devices in clinics around
the country. By increasing the number of early diagnoses—especially among vulnerable groups
such as children and people living with HIV—deaths associated with tuberculosis dropped, too.
Ssengooba saw this as a major success and wanted to deploy more machines. But it was hard to
make politicians aware of the technology’s power.
Then COVID arrived. Not long after the first case was reported
in Uganda on March 21, 2020, Ssengooba received a message from
a commissioner under the Ministry of Health. It had quickly
become apparent that most of the new cases were coming through
the border crossings, so screening people there would be a prior-
ity. Could Ssengooba make it possible to test everyone who wanted
to enter Uganda? His entire country was counting on him.
Ssengooba and his team began facilitating the collection of
nasal swabs taken from truckers at popular entry points, where
imported goods are brought into the landlocked country. Thosesamples—sometimes more than 1,000 a day—then needed to be
shuttled 150 miles to Kampala. The capital city was the nearest
place with laboratory technology set up to run a process known as
polymerase chain reaction—or PCR. Using fluorescent probes that
latch onto portions of the coronavirus genetic sequence, these mas-
sive machines could determine whether a sample was positive for
the genetic material of SARS-CoV-2.
Ssengooba’s team had to shuttle the samples themselves. A crew
of about 50 workers collected the samples in pickup trucks and
delivered them to the lab, then turned around to go back for theCOVID Set
Off a Boom
in Diagnostics
The pandemic accelerated the development of cutting-edge
PCR tests—and made the need for them urgent By Roxanne Khamsi