When Jessica was visiting the pediatrician with her nine-month-old daughter, they were suddenly asked to leave the general waiting room and hurried into another room. The reason: A child with a measles infection had come to the practice.

"We were not allowed to leave the room until everything was well ventilated and disinfected," Jessica said.

That experience impressed on the young mother: "The feeling of knowing an infected child is close and my child still has no protection, that's terrible. After the visit I searched my daughter for signs of measles every day, for fear she could have been infected."

Fortunately that didn't happen. Today the little girl is 18 months old, has been vaccinated for a long time and is old enough for kindergarten — but Jessica wants to wait, because she will soon have her second child. Until the new baby is vaccinated, she doesn't want to take any risks.

"The baby could get infected anywhere, I am aware of that. But the risk that we come into contact with measles in kindergarten is simply too great for me".

Many parents share Jessica's feelings. They have who children are too young for the first measles shot which in Germany is usually administered between the eleventh and fourteenth month. Until then, some parents don't dare take their babies to meet with friends who have kids. The also avoid school or kindergarten. And even those who do meet others are often worried. Are their fears exaggerated? 

Read more: Italy cracks down on unvaccinated schoolchildren

Main carriers are older children, adolescents and adults.

"Yes, that's exaggerated", Berlin-based pediatrician Dr. Martin Terhardt told DW.

In contrast to other countries, the number of measles cases in Germany has declined in recent years and is currently at a relatively low level. Measles cases are also limited to certain regions. Nevertheless, the doctor can understand the concerns of parents like Jessica, as the disease is highly contagious. 

"Measles is one of the most contagious diseases of all. It is assumed that the presence in the same room is sufficient to get infected, even if there is no contact with droplets from coughingor sneezing," Terhardt told DW. "There are studies that have shown that 95 out of 100 non-vaccinated people become infected. This is not the case for other diseases."

Those numbers go for people in a closed room with a measles patient. 

In keeping with Jessica's experience with her little daughter, Terhardt considers doctors' practices to be the place where most infections occur. 

During a major outbreak, like the one that occurred in Berlin in 2015, it can be a risk to take unvaccinated children into public transport, especially into the subway. But the Berlin outbreak also showed that measles is usually introduced by adults, not by children.

"In 2015, the disease spread primarily among older children, older adolescents and adults," Terhardt said. "Unfortunately at that time small children were also infected in pediatric practices, by adolescents." 

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Should vaccinations be administered earlier?

During major outbreaks, children can be vaccinated before they reach their eleventh month.

"The vaccines have been tested and approved in Germany and Europe for children who are at least nine months old," Dr. Terhardt said.

In addition to his work in his Berlin practice, the pediatrician has also been a member of the German permanent vaccination commission (STIKO) since 2011. The commission is responsible for drawing up vaccination recommendations in Germany.

"We are vaccinating according to rules that are valid for Germany, but there are some developing countries in which only the single measles vaccine, rather than the combined vaccine against measles, mumps and rubella, is given from six months on," Terhardt said. "There is practically no experience worldwide for children younger than that."

The younger the children are, the greater the risk they may have an undetected immune deficiency. For such children, a vaccination against measles would be dangerous because it is a live vaccine consisting of weakened viruses.

Another argument that speaks against vaccinating very young children: Maternal passive immunity. A baby's first immunity consists of maternal antibodies that the child receives through the placenta. But this only works if the mother actually had the measles or has been vaccinated. If that's the case, children are protected from infection for the first few months after birth.

"If, for example, children between the ages of six and nine months were vaccinated during a measles outbreak, which is not permitted in Germany, one could not be sure that the vaccination offers additional protection at all. The maternal antibodies could fend off the vaccine," Terhardt said.

However, mothers who neither had measles, nor were vaccinated can provide no protection at all. Their children are at risk of contracting measles from the moment they're born, because they have no maternal passive immunity.

Read more: Malaria vaccination: Paving the way to immunity

Maternal passive immunity is getting weaker

This inherited immunity, which protects small children from disease, is no longer what it used to be. Paradoxically, this is due to measles vaccinations. On average, vaccinated mothers pass on considerably fewer antibodies to their children than mothers who actually had measles. Maternal passive immunity also wears off quicker.

"This is a big problem and also the reason why we currently have so many cases in which even small children become infected," Terhardt said.

There are discussions in the STIKO vaccination commission that the initial 11-month wait period before the first vaccination period should be cut down a little.

A possibility that Jessica would consider for her second child: "I think I would have the baby vaccinated early if it was possible. I'd like to be able to attend courses or groups where, for example, older siblings are present, without worrying." 

Read more: Measles: Millions of children worldwide missed first vaccine, says UN

The best protection is a high vaccination coverage

According to Terhardt, however, it is still completely open whether an earlier date for the first measles shot will ever become reality in Germany.

"We are not able to make that decision quite yet, because we have to carefully examine all the literature for evidence before we recommend something like this to the whole population," the pediatrician said. "We haven't gotten that far yet." 

Which is why a high vaccination coverage is all the more important to him. Anyone who is old and healthy enough to be vaccinated should be vaccinated. This is especially true for women who want to become pregnant.

"These women should definitely check their vaccination status, talk to their gynecologist about the need to refresh their measles vaccine protection," Terhardt said. "When you're pregnant it's too late. You have to do this before pregnancy. Gynecologists have to be on board!" 

The same applies to all other doctors. Vaccinations should become a priority and should be addressed emphatically during every treatment. After all, it's not just children who are missing their shots.

According to the Robert Koch Institute, there were 392 measles cases in Germany by the middle of May 2019. Only 25 of these cases involved children younger than one year of age. 

Terhardt therefore recommends that young parents keep calm: "We do not have a high number of measles cases in Germany".

During an outbreak, however, one should be more cautious and for example call and ask for a separate waiting room before visiting a pediatrician with an infant.