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Friday, September 27, 2019

Technology eliminates cold storage for Chikungunya vaccine

By Esther Nakkazi

Most of the vaccines we use require cold chain storage to preserve them. Now a new type of vaccine technology that does not require this for the mosquito-borne virus Chikungunya vaccine has been developed says a press release from the University of Bristol. 

The vaccine can be stored at warmer temperatures, removing the need for refrigeration, has been developed for mosquito-borne virus Chikungunya. 

The findings, published in Science Advances, reveal exceptionally promising results for the Chikungunya vaccine candidate, which has been engineered using a synthetic protein scaffold that could revolutionize the way vaccines are designed, produced and stored.

Chikungunya, a virus transmitted by the bite of an infected mosquito causes crippling headache, vomiting, swelling of limbs and can lead to death. Even if a fever ends abruptly, chronic symptoms such as intense joint pain, insomnia, and extreme prostration remain. 

Formerly confined to sub-Saharan Africa, Chikungunya has recently spread worldwide as its mosquito host leaves its natural habitat due to deforestation and climate change, with recent outbreaks in the USA and Europe causing alarm.

Researchers from the University of Bristol and the French National Centre for Scientific Research (CNRS) in Grenoble, France, teamed up with computer technology giant Oracle to find a way to make vaccines that are thermostable (able to withstand warm temperatures), can be designed quickly and are easily produced.

“We were working with a protein that forms a multimeric particle resembling a virus but is completely safe because it has no genetic material inside, said Pascal Fender, an expert virologist at CNRS. 

“Completely by chance, we discovered that this particle was incredibly stable even after months, without refrigeration.”

“This particle has a very flexible, exposed surface that can be easily engineered, added Imre Berger, Director of the Max Planck-Bristol Centre for Minimal Biology in Bristol. “We figured that we could insert small, harmless bits of Chikungunya to generate a virus-like mimic we could potentially use as a vaccine.”

To validate their design, the scientists employed cryo-electron microscopy, a powerful new technique recently installed in Bristol’s state-of-the-art microscopy facility headed by Christiane Schaffitzel, co-author of the study. Cryo-EM yields very large data sets from which the structure of a sample can be determined at near-atomic resolution, requiring massive parallel computing.

Enabled by Oracle’s high-performance cloud infrastructure, the team developed a novel computational approach to create an accurate digital model of the synthetic vaccine. University of Bristol IT specialists Christopher Woods and Matt Williams, together with colleagues at Oracle, implemented software packages seamlessly on the cloud in this pioneering effort.

Christopher explained: “We were able to process the large data sets obtained by the microscope on the cloud in a fraction of the time and at a much lower cost than previously thought possible.”

“ Going forward, technologies like machine learning and cloud computing will play a significant part in the scientific world, and we are delighted we could help the researchers with this important discovery,” added Phil Bates, leading cloud architect at Oracle.

The particles the scientists designed yielded exceptionally promising results in animal studies, soundly setting the stage for a future vaccine to combat Chikungunya disease.

“We were thoroughly delighted,” continued Imre Berger. “Viruses are waiting to strike, and we need to have the tools ready to tackle this global threat. Our vaccine candidate is easy to manufacture, extremely stable and elicits a powerful immune response. It can be stored and transported without refrigeration to countries and patients where it is most needed. Intriguingly, we can now rapidly engineer similar vaccines to combat many other infectious diseases just as well.”

“It really ticks a lot of boxes,” concluded Fred Garzoni, founder of Imophoron Ltd, a Bristol biotech start-up developing new vaccines derived from the present work. “Many challenges in the industry require innovative solutions, to bring powerful new vaccines to patients. Matching cutting-edge synthetic biology with cloud computing turned out to be a winner.”

Paper

‘Synthetic self-assembling ADDomer platform for highly efficient vaccination by genetically-encoded multi-epitope display’ byVragniau et al in Science Advances

Traditional healers super-spreaders of Ebola in DR Congo

By Esther Nakkazi

A 39-year-old woman, a traditional healer, who died in the Salama Health Area in the Madidi district is the new validated case for Ebola Virus Disease in the Democratic Republic of Congo (DRC).

The woman’s death would have been treated like any other but she is a traditional healer and the DRC Ministry of Health has observed the role they play in the transmission of Ebola.

“Traditional health practitioners play a key role in the transmission of the Ebola. Their transmission is by nosocomial infection,”observed the Ministry of health, DRC in a statement it issued in December 2018.

Nosocomial infection is an infection that is acquired in a hospital or other healthcare facility and is spread to the susceptible patient in the clinical setting by various means. The DRC ministry of health officials said a parallel consequence of these nosocomial infections is the contamination of a large number of healthcare providers.

Traditional healers are well-known, widely respected and they remain the health providers of choice in their communities. As such, they remain the first point of contact for some Ebola patients before they consider crossing over to a hospital or health care clinic.

Being a traditional healer, this woman had 45 contacts around her, 3 of whom confirmed positive for Ebola - her husband, mother and son, all admitted to Komanda Ebola Treatment Centre or Centres de Traitement d’Ebola (CTE).

But before that even as a confirmed Ebola case this woman and her family refused to go to a CTE and preferred to self-medicate herself until she had advanced symptoms of Ebola. She was later rushed and hospitalised at the Saint-Pierre Medical Center.

At the Saint-Pierre Medical Center, her case was confirmed and referred to a CTE. Health workers tried to persuade her and her family to go to the ETC but her family outrightly refused.

“The patient was brought home by her family on September 6, where she died at around 10 pm. Oral sampling and dignified and secure burial did not occur by refusal of his family,” said a report from the Ministry of Health, DRC.

Since the beginning of the epidemic, the cumulative number of cases is 3,168, of which 3,057 are confirmed and 111 are probable. In total, there were 2.118 deaths (2007 confirmed and 111 probable) and 975 people healed.

Since vaccination began on August 8, 2018, 227,230 people have been vaccinated. On 25th September 2019, an emergency vaccination was launched in Kisansha. During the 9 days 825,000 children from 6 to 59 months in 24 health zones in the provinces of Equator, Mongala, Kwilu, Kwango, Mai-Ndombe and Kasai Oriental would be immunized.

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Friday, September 13, 2019

Kenya starts Malaria vaccine trial

Kenya has launched the world’s first malaria vaccine today in Homa Bay County, western Kenya.

The malaria vaccine pilot programme is now fully underway in Africa, as Kenya joins Ghana and Malawi to introduce the landmark vaccine as a tool against a disease that continues to affect millions of children in Africa, says the World Health Organisation.

The vaccine, known as RTS,S, will be available to children from 6 months of age in selected areas of the country in a phased pilot introduction. It is the first and only vaccine to significantly reduce malaria in children, including life-threatening malaria.

Malaria claims the life of one child every two minutes. The disease is a leading killer of children younger than 5 years in Kenya.

“Africa has witnessed a recent surge in the number of malaria cases and deaths. This threatens the gains in the fight against malaria made in the past two decades,” said Dr. Matshidiso Moeti, WHO Regional Director for Africa.

“The ongoing pilots will provide the key information and data to inform a WHO policy on the broader use of the vaccine in sub-Saharan Africa. If introduced widely, the vaccine has the potential to save tens of thousands of lives.”

First vaccination: a day to celebrate

Distinguished health officials, community leaders and health advocates gathered in Homa Bay County – one of eight counties in Kenya where the vaccine will be introduced in selected areas – to mark this historic moment with declarations of support for the promising new malaria prevention tool and to demonstrate a ceremonial first vaccination of a 6-month-old child.

“Vaccines are powerful tools that effectively reach and better protect the health of children who may not have immediate access to the doctors, nurses and health facilities they need to save them when severe illness comes. This is a day to celebrate as we begin to learn more about what this vaccine can do to change the trajectory of malaria through childhood vaccination,” said Dr. Rudi Eggers the WHO Representative to Kenya.

Thirty years in the making, the vaccine is a complementary malaria control tool – to be added to the core package of WHO-recommended measures for malaria prevention, including the routine use of insecticide-treated bed nets, indoor spraying with insecticides and timely access to malaria testing and treatment.

Malaria vaccine implementation in Kenya
The Ministry of Health, through the National Vaccines and Immunization Programme, is leading the phased vaccine introduction in areas of high malaria transmission, where the vaccine can have the greatest impact.

The aim is to vaccinate about 120 000 children per year in Kenya across the selected introduction areas, including Homa Bay, Kisumu, Migori, Siaya, Busia, Bungoma, Vihiga and Kakamega counties.

Within the eight counties, some sub-counties will introduce the vaccine into immunization schedules while others are expected to introduce the vaccine later.

Thursday, September 5, 2019

Study says fetching water increases risk of childhood death

By Esther Nakkazi

Growing up in the city I did not fetch water but for the few times that I visited my lovely grandma (R.I.P Margaret Njakasi) I had to participate in the activity. It was very much for the younger children and maybe one adult who would carry a big (20 litres) jerrycan.

I loved the experience because it was time to play. The water source was downhill. We went in a group of about 6 from my grandma’s house and we would run all the way. We would quickly line up our water containers and run uphill in a queue and slide down sometimes soiling our clothes while some children did it on bare bottoms.

The time we had to spend depended on how enjoyable the ‘sliding’ was and pretty much of the time it was epic - the shouting when you were sliding to the bottom and the cheers plus the climb to go back up and come through again.

Now new research from the University of East Anglia in the UK says water fetching is associated with poor health outcomes for women and children and a higher risk of death.

Adults collecting water is associated with increased risk of childhood death, and children collecting water is associated with increased risk of diarrheal disease, says the study.

The study entitled ‘The association of water carriage, water supply and sanitation usage with maternal and child health. A combined analysis of 49 Multiple Indicator Cluster Surveys from 41 countries’ is published in the International Journal of Hygiene and Environmental Health on Tuesday, September 7, 2019.

The study links women collecting water to maternal health saying if a woman has to collect water chances of giving birth in a health care facility are reduced. The study found that women or girls who have to collect water have reduced uptake of antenatal care and increased odds of leaving young children under five alone for an hour or more.

Researchers studied health outcomes including the risk of child deaths, diarrhoea in children under five, low child weight and height, the number of women giving birth in a health care facility, the uptake of antenatal care and whether young children were being left alone for long periods.

Prof Paul Hunter, from UEA’s Norwich Medical School, the Principal Investigator said not much has been known about the health outcomes of fetching water. “We wanted to find out more about the health implications of fetching water, as well as the outcomes of using unsafe water supplies, inadequate access to improved sanitation – particularly in relation to the health of women and children,” he said.

The research, which involved more than 2.7 million people in 41 countries, is the first to analyse the relationships between water carriage, access to clean drinking water, sanitation and maternal and child health using the UNICEF multiple indicator cluster survey data.

Prof Hunter and his co-investigator Dr Jo Geere, from UEA’s School of Health Sciences, studied data from more than 2.7 million people in 41 low to middle-income countries, looking for associations between access to drinking water, sanitation and health.

Besides women who fetch water’s reduced chances of giving birth in a health care facility, they also have a low uptake of antenatal care and because they have to go to the water source they leave their children under five alone at home for over an hour or go with them. If they are left at home alone unsupervised the children get in trouble.

For the time it takes to walk to a water source, queue up, collect the water and return. Unsupervised children are likely to be at more risk of death from accidental injury or simply from reduced parental care when it is needed – for example during illness or when they are very young, said Dr. Jo Geere, a co-investigator to the study.

“Alternatively, if mothers take their young child with them to collect water, the route may be unsafe due to extreme environmental conditions, hazardous traffic, or interpersonal violence.

“Fetching water may also exacerbate under-nutrition which may inturn impact pregnancies and breastfeeding – increasing the risk of child mortality. And many of the studies we looked at reported fatigue and tiredness affecting water carriers,” said Dr. Geere.

The researchers also found that improving access to water and sanitation is associated with better health outcomes for women and children. This is consistent with another study from Ethiopia, which showed that when taps were installed closer to home, the monthly risk of child death was 50 percent lower among children of the women with access to the new taps.

“This really shows the difference that improved access to clean water makes,”” said Prof Hunter. “Living in a household without a flush toilet was associated with a 9-12 percent higher risk of child death than living in a household where members usually used flush toilets.

Having access to water in homes and having good sanitation led to big improvements to the health of women and children. As such children born into communities with improved sanitation were 12 per cent less likely to die than those born into communities with poor sanitation,” said Prof Hunter.

The research does not specify for how long you have to carry the water and in what way either on the head or lifting jerrycans.
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