Detection of emerging and re-emerging infections is important both locally and internationally, with the potential for rapid and global dissemination of infectious  agents. Our work depends on extensive surveillance platforms and close collaboration with local and international partners to identify and respond to disease outbreaks.

We have a long-standing collaboration with the US Centers for Disease Control and Prevention, which hasenabled us to build platforms to track infections, through hospital-based surveillance and population-based surveys.

We use our understanding of likely routes of transmission to develop new interventions. We aim to identify methods that are practical and affordable, and thus suitable for |wider scale-up.

We routinely respond to infectious disease outbreaks in Bangladesh in partnership with the Institute of Epidemiology, Disease Control and Research (IEDCR), and in collaboration with the local One Health initiative.

Pesticide poisoning

Investigation of an acute encephalitis syndrome (AES) outbreak, which led to thf deaths of 13 out of 14 affected children in northern Bangladesh, identified pesticides as the likely cause. Regular AES outbreaks near lychee orchards occur across Asia, but the precise cause of illness is unclear. An outbreak investigation carried out by icddr,b, IEDCR and US colleagues found that visiting a lychee orchard or a garden using pesticides was associated with AES but consuming lychees was not; several powerful pesticides, including some banned in many countrieg, were used in the orchards investigated.

The results are not consistent with a recent suggestion that toxins in lychees themselves are responsible for AES outbreaks.

Ubiquitous dengue

A study has found that dengue virus'a infections are remarkably commoflH in Dhaka, and identified a range of | factors increasing the risk of infection including the cultivation of indoor potted plants which provide breeding opportunities for mosquitoes.

icddr,b researchers and colleagues from Canada and the US tested for antibodies to dengue virus in Dhaka residents before and after the monsoon season. Around 80% of participants showed signs of infection in the pre-monsoon survey, while more than half-of those not previously infected tested positive after the monsoon, suggesting widespread circulation of the virus in the intervening period. The results suggest that many cases of dengue-associated illness may be going unreported, and rthat mosquito control measures such as removing indoor potted plants could reduce the spread of the virus.

Guillain-barre syndrome

A small pilot study has explored the feasibility of a low-cost treatment for Guillain-Barre syndrome (GBS), a rare neurological disorder triggered by Infection with Campylobacter jejuni.

GBS appears to be particularly severe in Bangladesh . However, conventional treatments are generally out of reach for financial reasons. icddr,b researchers have developed a practical and low-cost alternative, small volume plasma exchange. A pilot feasibility study suggests it may be a safe and cost- effective alternative.

Nipah transmission

Contaminated towels and bed sheets have been shown to be a potentially important route by which Nipah virus is transmitted from hospitalized patients. Although most cases of Nipah infection are linked to consumption of contaminated date palm sap, nearly one-third of patients are infected by patient-to-patient transmission. The results point to possible targets for improved infection control to reduce the risk of transmission.

The team is currently testing infection control packages in public hospital settings to the reduce risk of person-to- person transmission from suspected Nipah patients to healthcare workers and caregivers.

Avian flu

Nomadic ducks - domestic ducks moved between feeding grounds during the year - have been identified as a potentially important conduit for the spread of H5 or other avian influenza viruses from wild bird to domestic poultry populations. Some 30% of egg yolks tested were positive for H5 antibodies and 94% of flocks had at least one egg with such antibodies.

In other studies, a recently introduced H5N1 avian influenza substrain was found to be responsible for an outbreak that killed substantial' numbers of wildfowl, chickens and geese in northeastern Bangladesh in 2011. Furthermore, population- based surveillance identified two cases of human H5N1 infections, suggesting that undetected infections may be occurring in Bangladesh and emphasising the need for survei lla nee for mild respiratory disease among populations exposed to infected poultry.

Drug-resistant TB

icddr,b researchers completed a six-year drug-resistant tuberculosis (TB) surveillance project in 2017 - the first undertaken in the WHO South- East Asia region. The surveillance sites spanned 20 districts across all Bangladesh. The overall rate of drug resistance was found to be 3.2%.

The rate was lower (2.3%) among the patients with no prior TB history and significantly higher (13.8%) among patients previously treated forTB.

Although the percentage of drug- resistant primary TB cases is relatively low (2.3%), this still translates to around 5,000 cases, representing a significant public health challenge. These findings, together with those from the national drug resistance survey conducted by the National Tuberculosis Control Program, will inform future policies to contain this epidemic.

Report 2017