Gallery: Innovative vaccine against rotavirus, Niger

21 March 2017

This slideshow explains the challenges posed by rotavirus and the existing constraints of the existing vaccines. It shows the story of the Epicentre study in Maradi district, Niger. The vaccine is now proven safe and effective. Last step: prequalification by World Health Organization (WHO).

Photo: Séverine Bonnet/MSF

Today, diarrhoea is still the second biggest killer of infants and children in the world. Rotavirus infection is the leading cause of severe diarrhoea, which kills an estimated 1,300 children globally each day.

Photo: Séverine Bonnet/MSF

Most of these deaths occur in low-income countries, in places where access to water and sanitation is limited and people can't access life-saving medical care for their children. In such situations, preventive measures such as vaccinations have an enormous impact.

Photo: Séverine Bonnet/MSF

Aziz Adoulay, coordinator of a team of 122 field workers, carries out awareness-raising activities in Madarounfa, one of the 200 villages participating in the clinical study. More than 4,000 children were initially included in this study after their parents had provided informed and written consent.

Photo: Séverine Bonnet/MSF

The vaccine is made by the Serum Institute of India, using five strains of the virus collected exclusively in sub-Saharan Africa. It has a special characteristic: it is heat-resistant (thermostable at 37°C for between six months and a year). Unlike the majority of vaccines, which must be kept in refrigerators at between 2°C and 8°C, this new vaccine can be kept at room temperature and can tolerate temperatures up to 37°C (for between six months and one year) without losing its properties. At the Epicentre office in Maradi, the vaccines are stored in the pharmacy before being sent out to the health centres where the study is taking place.

Photo: Séverine Bonnet/MSF

To guarantee the effectiveness of the existing vaccines against rotavirus, they must be stored and transported in strict conformity with cold-chain rules, like many other vaccines. They must be kept in freezers at between 2°C and 8°C. This requires a considerable logistical effort, as well as equipment that can be costly and uses electricity or fuel. This is a major obstacle in a country such as Niger, where the health centres in rural areas do not have all of this equipment.

Photo: Séverine Bonnet/MSF

Every weekend, the five health centres report on their stock levels and requirements so that all of the necessary vaccines can be delivered to them in simple insulated boxes. The vaccine dose and syringe are quick to prepare: they come packaged in a single box measuring just over 5cm. Thanks to the small size of the packaging, the vaccines are very easy to store and transport.

Photo: Séverine Bonnet/MSF

Mohamed Zakari receives his first dose of the oral rotavirus vaccine (or the placebo). He is eight weeks old, the cut-off age for participants in the clinical trial. If his mother, Hadiza Souley, had brought him one day later, Mohamed would have been excluded from the trial in order to comply with the medical protocol. Mohamed will receive the second and third doses of the vaccine at 10 and 14 weeks respectively. During the course of the clinical trial, from birth to the age of two years, Mohamed will be monitored 12 times. At these scheduled medical appointments, various blood, urine and stool specimens will be taken. At his 10-week appointment, Mohamed will also be vaccinated against eight antigens: polio, Pentavalent 2, whooping cough, hepatitis B, diphtheria and tetanus. His mother has been participating in the clinical study since she was 20 weeks pregnant and was monitored by the medical team at four scheduled appointments during her pregnancy. She is still being monitored and the quality of her breast milk is checked to lower the risk of the newborn being malnourished. Here, Hassan, a nurse at the Madarounfa health centre, collects the various specimens.

Photo: Séverine Bonnet/MSF

In parallel with the study into a new rotavirus vaccine, more than 1,000 pregnant women are being monitored as part of a sub-study to evaluate the impact of the nutritional condition of pregnant women on the health of their babies. The women receive nutritional supplements and attend four scheduled appointments with the medical team for monitoring purposes. Vaginal swabs, blood specimens (to test for malaria, thick smear, syphilis and HIV /AIDS) and urine and stool specimens are taken. The women also give permission for their newborns to be included in the study and monitored for two years by the Epicentre medical teams. At each appointment, the mothers receive a transport allowance, three bars of soap and a food parcel containing bread, a drink and a tin of sardines.

Photo: Séverine Bonnet/MSF

The files of the patients undergoing treatment are stored at the health centre itself. For data protection reasons, a special coding system is used.

Photo: Séverine Bonnet/MSF

If there are inconsistencies in the data, the monitoring team can send somebody out to the communities or to one of the five health centres, where teams of archivists also check that the information in the files is consistent. Anomalies are rare, but they can comprise inconsistencies regarding a patient's height versus his or her weight, or the dates of the scheduled appointments versus the age of the child, or missing data. Every correction is documented and explained.

Photo: Séverine Bonnet/MSF

Ten-week-old Nana Hanissa receives her second dose of the rotavirus vaccine (or placebo). She will be given the third and final dose at 14 weeks of age.

Photo: Séverine Bonnet /MSF

The quicker this new vaccine is prequalified by the WHO, the sooner it can be used to prevent the deaths of thousands of children in the countries where it is most needed.

Photo: Séverine Bonnet/MSF

In the laboratory of Maradi, a team of a dozen people receive about 1,200 specimens (blood, urine, stools, mothers' breast milk...) every week, to be analysed for the trial. The specimens are taken in the morning, either by the medical teams at the five health centres involved in the study, field workers or assistant nurses at the patients' homes. They arrive at the laboratory in Maradi in the early afternoon. Four samples are necessary to meet the requirements of the protocol. One sample is for the rotavirus test, another is for the laboratory in Cincinnati, USA (only if it tests positive for rotavirus) and the other two samples are kept in freezers (at between -85°C and -72°C) for the archives, in case they are needed later.