[ad_1]
As part of a catch-up vaccination campaign because of South Africa’s five-month-long measles outbreak, all children between the ages of six months and 15 years can get a free vaccine in the public sector. This is even if they’ve missed a jab in the past (or their parents can’t remember if they had all their shots) or if they no longer have a vaccination card, says the National Institute for Communicable Diseases (NICD).
Measles is a highly contagious disease that spreads when people breathe in tiny virus-containing droplets that hang in the air when an infected person coughs or sneezes. People can also get the virus if they touch a surface onto which these droplets have fallen and then touch their nose, mouth or eyes.
It’s especially children under the age of five who get infected or fall seriously ill. Although only one or two out of every 1 000 children will die from measles, getting infected with the virus can cause other complications like an ear infection which occurs in one in every six children. In serious cases, infection can cause brain damage and deafness.
In the state sector, measles vaccines are given to infants at six months and one year and a catch-up jab is available for children under five who’ve missed one of these shots.
It’s this catch-up dose that’s available now, as long as it’s been more than a month since their previous jab, says Jack Manamela, an epidemiologist from the NICD.
The national vaccination campaign comes on the heels of South Africa’s biggest measles outbreak since 2009. Then, more than 18 000 cases were recorded in almost 24 months.
The outbreak started in October and has affected five out of nine provinces (Gauteng, Limpopo, North West, Mpumalanga and Free State). By 2 February, the NICD’s laboratory tests had confirmed 441 cases. Many of the cases (about 40%) are in children between the ages of five and nine years, with children under five years and those between 10 and 14 also being affected, the NICD’s data shows.
That is why the vaccination campaign only includes people up to 15 years. Measles outbreaks occur when vaccine coverage rates aren’t high enough, leaving children unprotected against infection and a chance for the virus to spread.
South Africa usually has a few measles cases in a year, like 12 that occurred in 2020, for example. But the NICD only calls an uptick in cases an “outbreak” when there are three or more patients (confirmed by lab tests) in the same area within a month and they are linked to each other, says Michelle Groome, who heads the NICD team that monitors and responds to public health issues. Another 18 confirmed cases aren’t included in the 441 that make up the current outbreak tally, because they aren’t connected to each other and are in provinces that haven’t declared an outbreak.
There’s no specific treatment for measles — doctors usually just manage a patient’s symptoms — but the disease can be prevented almost completely with vaccines.
Health workers and people older than 15 years with underlying diseases that weaken their immune system, and therefore are more likely to fall seriously ill with measles, aren’t included in the vaccination drive but a doctor will be able to tell them whether they need extra protection from a vaccine, explains Kerrigan McCarthy, a pathologist in the NICD’s vaccines team.
We unpack the NICD team’s insights shared during a recent Facebook live session about the outbreak.
- Why is there a measles outbreak now?
South Africa hasn’t been able to vaccinate enough children against measles to stop it from spreading between people, Manamela says. To eliminate the disease, 95% of children have to be vaccinated, the World Health Organisation recommends.
Two doses of the vaccine between the ages of six months and two years will cut a child’s chances of getting measles by at least 95%. The protection from two jabs lasts a lifetime.
At government clinics, people can get a measles-only shot (called MeasBio) for free, while in the private sector they can get a three-in-one jab against measles, mumps and rubella (German measles) for about R275.
Data from 2015 to 2020 shows that South Africa managed to eliminate the disease — defined as having less than one case per million people — in 2015, 2016 and 2020. This was because of high vaccination rates in 2015 and 2016, while the lockdown and social distancing measures contributed to fewer cases in 2020.
In 2019, just 80% of children had gotten two measles jabs, according to a health department survey. This “immunity gap” results in outbreaks about every six years, researchers found.
The current outbreak, says Manamela, is a result of babies having missed their shots during COVID lockdowns, when their caregivers couldn’t get them to vaccination clinics and because parents were worried their children would get COVID if they took them to a hospital or clinic.
At the moment, our vaccination rate is between 75% and 80%, McCarthy estimates — which is far off the ideal target of 95%.
- Why do so many people have to be vaccinated to stop measles?
In an unvaccinated group of people, measles spreads very fast.
Nine out of 10 unprotected people who get infected will fall ill, and each person will spread the virus to between 12 and 18 others.
But when the measles virus reaches someone who is immune — either because of vaccination or previous infection — it mostly can’t spread any further.
The jab prevents infection and serious illness, says Groome. This is different from how Covid vaccines work — they’re better at stopping people from getting seriously ill. The protection of measles jabs also lasts for much longer than immunity from Covid shots, adds McCarthy — lifelong for measles compared with a few months for Covid.
Because the measles virus is so contagious, Groome explains, having even small pockets of people who are not immune will allow the germ to spread and lead to a lot more cases.
- Did Covid play a role in South Africa’s poor vaccination rate?
Yes.
Overall, it doesn’t look like there was much of a difference in people who got both measles shots during Covid. It seems to stay steady between 2019 (82%) and 2020 (81%), according to data presented in parliament in June 2022.
But zooming into the details changes the picture somewhat.
The national figures show that 84% of children got their first shot of two in 2019, just less than 85% in 2020, and 87.5% in 2021.
But the number of children who got their second jab dropped: from 80% in 2019 to 77% in 2020. Vaccination increased to 82% again in 2021.
The second measles jab is crucial — it gives a huge hike in protection. Children who get only one dose are five times more likely to get infected with measles than those who get both.
In five provinces (Gauteng, Eastern Cape, Mpumalanga, Northern Cape and North West) vaccination rates or getting both rounds of vaccination dropped in 2020.
Numbers picked up again in 2021, probably because of the health department’s catch-up efforts started towards the end of 2020.
- Is the problem unique to South Africa?
No.
Around the world, 40 million children missed one of their measles vaccinations in 2021, according to a Centres for Disease Control (CDC) report.
In Zimbabwe last year, an outbreak resulted in 6 551 children getting infected. There, 85% of children had had at least one jab. But the number of new cases has dropped significantly since the Zimbabwean government rolled out a vaccine campaign in August, McCarthy says, with only 1 299 new cases being recorded between September and January.
Also, a report from the CDC shows that between 2016 and 2018, measles cases more than doubled worldwide.
There were similar outbreaks in Europe between 2016 and 2018, McCarthy says. For example, Romania had about 18 000 cases of measles, which were mainly in unvaccinated children. Their vaccination coverage rate was estimated to be 81% at the time.
- Why aren’t other childhood diseases increasing in a similar way?
Measles spreads much faster than other childhood diseases which can also be prevented through immunisation, explains McCarthy.
For example, if someone is infected with the virus that causes rubella, they will pass the bug on to between five and 10 others, whereas a person with measles will spread it to between 12 to 18 others). (Rubella looks almost like measles, because it also causes a red rash, which may be slightly itchy, and a fever with mild symptoms but it’s generally not as bad as measles.)
So, if both viruses are circulating in a community, measles is going to reach unvaccinated or partially vaccinated people faster.
It could also be that the “immunity gap” for measles is bigger than for other childhood diseases because of the way South Africa’s childhood vaccine programme is set up, says McCarthy.
Babies get most of their vaccines in groups. At 14 weeks, for instance, babies get three jabs that protect them against eight infections (including viral diarrhoea, polio, whooping cough and pneumonia).
But parents have to make two trips to the clinic to make sure their children get both measles jabs — once at six months and then again by their child’s first birthday — which might be hard for them to do.
That said, South Africa is also seeing an increase in pertussis (whooping cough), another vaccine-preventable disease, although it’s not as transmissible as measles, so case numbers are lower.
- What side effects can someone expect after getting vaccinated?
The measles shot is a live attenuated vaccine (like the rotavirus and chickenpox jabs), which means it contains a weakened form of the actual virus to prompt the body to make antibodies to fight the virus without causing severe disease. This is different from an mRNA vaccine, for example, which we used against Covid.
McCarthy says that this has both an advantage and a disadvantage.
“This type of vaccine [one that contains live attenuated virus] elicits a strong immune response, so one will almost never get measles if you’ve had the jab. But because it mimics an actual measles infection, it might feel almost as if you did actually get infected, but just in a very mild way.”
But these side effects are usually mild, unlike the serious complications that can occur with natural infection.
For this reason, about one in 20 children might get a fever after having had their shots and one in 100 might develop a rash, says McCarthy.
Brain infection occurs in one in 2 million cases, which makes it a very rare side effect.
- How would I know if my child had measles?
It takes between 10 and 14 days for someone to develop symptoms after they’ve been infected.
Early symptoms include a fever and a red rash that isn’t painful or itchy. Children may also have a cough and red eyes.
Groome says: “It’s important to treat a fever, and if any symptoms worsen, take your child to a healthcare professional — especially if they’ve not been vaccinated.”
The virus is also contagious from four days before the rash starts until four days after.
- Can you get vaccinated if you have measles symptoms?
No, says Groome.
Children should not be vaccinated if they have any moderate or severe illness. This is because it might increase the chance of a side effect or interfere with the immune response, she says.
Groome says: “We don’t advocate that you give it to a child if they have symptoms. But if a diagnosis of measles isn’t confirmed, and the child is better, then the vaccine can be given.”
This story was produced by the Bhekisisa Centre for Health Journalism. Sign up for the newsletter.
[ad_2]
Source link
