Can You Vaccinate a Sick Child? Fever, Missed Vaccines & What Parents Should Know

Can you vaccinate your child when they’re sick? What happens if you miss a vaccine? And when should you worry about fever after vaccines?

These are some of the most common—and most important—questions parents ask.

In this episode of Healthy Beginnings, Dr. Edgar Kalimba breaks down real-life vaccine concerns that families face every day. From mild illness and missed doses to fever after vaccination, this episode gives you clear, practical answers grounded in evidence.

In this episode we discuss:

•  Whether it’s safe to vaccinate a child with a cold, cough, or fever 
•  What to do if your child has missed vaccines—and how catch-up schedules work 
•  Why vaccinated children can still get sick 
•  Fever after vaccines—what’s normal and when to seek medical help 

Vaccines are one of the most effective ways to protect children—but knowing how to navigate real-life situations can make all the difference.

Healthy Beginnings offers clear and evidence-based conversations about children’s health, family wellbeing, and the systems that shape our lives. 

New episodes every Monday 

Have a question? Email: healthybeginningspodcast@gmail.com

Produced by LF Media

Transcript

SPEAKER_01 0:00

So, welcome back to our conversation today on healthy beginnings. We started last time, last week, a discussion around vaccines, and I ran through uh key information that you know parents get concerned about with regard to vaccinating your baby or your child. And this week I would like to pick up um I'll call it part two of the vaccine discussion because this is a very important topic, and I would like to dive into some of the other common questions and practical questions that parents ask themselves about their real concerns, and understanding these uh answers can make a big difference in how confident you feel when making decisions for your child. So, my plan today is to cover mainly three uh areas. Uh, one is what happens when your child is sick and their date for the vaccine has actually arrived. Very common scenario, particularly for babies and children who go to preschool, who go to preschool, who go to crash, frequently they are sick, they are unwell. So, what happens? If my child has a runny nose, has a cough, has a mild fever, what do I do? Should I go get the vaccine or should I wait? And if I wait, what happens? Um, so if you miss a vaccine for one reason or another, can you catch up? That is the next discussion item. And then finally, we'll discuss around uh a bit more detail on vaccine-related side effects, particularly fever, and when should you be concerned for your baby? We will then discuss a little bit more on the next session with regard to uh the efficacy around vaccines. Because sometimes parents do ask, and rightly so. I got my child vaccinated with all the recommended and scheduled vaccines, but they still get sick. Why? Why does this happen? So that will be our part three of the vaccination discussion next week. So back to today, before I get into the first discussion item on should I still vaccinate my child when they are sick, I would like to briefly, very briefly discuss the physiology behind vaccines and how they work. And putting it simply, you know, vaccines work by training the immune system of your child. And the immune system gets trained to recognize a threat. That threat in this case is a disease. Um, so you're really trying to get your child's immune system to learn to recognize a threat and be able to respond to it without ever meeting the real infection, without ever being really sick before. And typically, what is injected or is given to your child when they get the vaccine is antigens or portions of these microbes in one form or another. And typically these are combined because most of the time the vaccines that we actually give are a combination of different vaccines, meaning they cover different diseases. I'll give an example. Uh, for the random vaccination calendar, what your child gets at six weeks, 10 weeks, and 14 weeks is a combination of actually five or even six vaccines, typically diphtheria, tetanus, patassus, uh, pneumococcal, um, hepatitis B, and polio. So those are actually a group of vaccines. So what happens is that these antigens, we refer to them as antigens most of the time, they are introduced into your child's system, to your child's body. And then the body looks at these threats, and naturally the immune system responds by making antibodies, which are the soldiers. And these antibodies uh play a very important role in terms of preparing the immune system to actually respond, or your child's immune system to respond appropriately. And part of these antibodies also form what we call memory cells. So the question now then is why do we need to give two, three, sometimes four doses of the same vaccine? And the and the simple reason is that the first dose uh triggers what we call a primary immune response. Means that your baby's immune system is meeting something for the first time, is meeting this adversary or this antigen for the first time, and uh they don't know exactly how to respond. And that's why the primary immune response is slower and smaller, meaning it creates a less robust immune response at the very beginning. However, it creates what we call a lasting memory, and this lasting memory or the memory cells is what actually makes it possible for them to respond better at the next trigger or which is the next vaccine or the next dose of the same antigen. So if we give, let's say, hepatitis B at six weeks, there will be a response. It might not be a very robust response, but when you introduce the next short or the booster at 10 weeks, the response this time from the immune system, because they will have met this antigen before, is faster and stronger. So it's much more robust. And then it also works as a reminder. It means that a booster or the next dose or the second, third, fourth doses are like reminders of the immune system that, hey, remember, this is how you should respond when you meet this adversary. So, in a way, vaccines train uh our bodies and our children's bodies to recognize antisms, recognize threats, and respond appropriately. And I'll come back to this uh when I talk about catch-up when you miss doses, because obviously it has an impact. So let me backtrack a bit now and get into the real discussion of today, which is can I vaccinate my child when they're sick? Typically, um, in environments and communities where babies are sent to crash or to play school to spend the day, you know, parents are busy, life is busy, so more and more families are sending their children to crash and to play school quite early on. And what happens is that, you know, they interact with other children and understandably they get sick more frequently. And then your vaccine schedule or date arrives and your baby's sick, and you wonder, so what do I do? And the short answer is it really depends on how sick your child is. And the general guideline and recommendation that we give is if your child has a mild illness, and when I say mild illness, I'll give examples. If your baby has a runny nose, very frequent in babies and children, or has a mild cough, or has a low grade fever, or maybe has mild diarrhea. I'm using the word mild because, you know, babies and children often have these symptoms, but they are playing, they have good energy, they are able to feed, and generally they look well despite these symptoms. So in these cases, it is very safe to vaccinate. Because when you skip vaccines or when you miss them, sometimes even at the next opportunity, they might still be sick or they might have something. And that snowballs into uh missed vaccines, and that could defeat the purpose and actually expose your baby and take away the opportunity for them to be protected. So, from what I described in terms of how vaccines work and how they prime and prompt and train the immune system, um having a mild illness, a runny nose, a mild cough, a low-grade fever does not really exclude, it's not a contraindication for your baby to get vaccinated, because mild illnesses do not interfere how the immune response happens, how your immune system, how your child's immune system responds to the vaccines. Um however, if your child has more moderate or severe symptoms, so if they have a high grade fever, you know, have very high fever, temperatures of 39, 40 degrees Celsius, if they are significantly sick, they are lethargic, they are barely able to feed, they are really struggling, they're miserable, um, or they have features of another serious infection, whether it's malaria or pneumonia or tonsillitis, something recurring antibiotics, this is usually better to wait until they recover. Now, it should be noted that it is better to wait not because the vaccines are dangerous in these situations, but because it might be harder to tell what is actually triggering the symptoms. Because vaccines can give symptoms, I'll come back to that. And how do you tell what is causing what? Is it are they getting more sick because of the vaccines that are added onto it? Or are they actually getting sicker from that illness or that sickness that they're having? So it's more of uh being cautious and being able to actually manage your child when they are sick than the vaccines themselves being dangerous. Um in that case, you know, if your child is actually uh significantly sick, you would rather wait. And of course, vaccines can cause discomfort, and uh your child is already sick with some moderate to severe symptoms, and you don't want to make them more miserable. You know, that's also a factor, you know, you really want your child to first recover, and then they can get the vaccines. So the key takeaway here is really that mild illness uh is usually okay to vaccinate, but more serious illness, you need to either seek your healthcare provider or consider postponing. Now that takes me to the next part of our conversation, which is can I catch up if I missed vaccines? Um life happens. Maybe you missed an appointment, you got busy and completely missed the appointment. You might have moved locations. This is very common. You know, there's many families that come and spend holidays here or back and forth between different countries. Um in the past, still in the present, there's still many mothers who probably go give birth in a different country, and then they move back here to Rwanda, and so on and so forth. So all kinds of things can happen. And the good news is that yes, you can catch up. And typically, what we do is we sit and look at your baby's vaccination schedule. How old are they? What have they actually received before? What was missed, and then we make up a catch-up plan. And most of the time, we do not need to restart. So let's say they were supposed to get three series of hepatitis B, they got one and then mixed the second and third boosters. Most of the time, we do not need to restart and to give what they got already. Most of the time, we actually do a catch-up and put a schedule to make sure that what was missed is given. So the doses that your child already received still count. And uh we most of the time simply pick up from where your child left off. And of course, we typically want to get your schedule and catch up as soon as possible because the longer you wait, the more you lose out, the more you expose your baby from what would be the protection given by the vaccines. Um, so doses are generally spaced safely and effectively, and they will still work. Um, timing does matter. Uh, some vaccines have minimum intervals between doses. So we would definitely typically guide you on how to correctly do the catch-up. So you just need to make sure that you have your child vaccination, and then uh you discuss this. Very feasible. So, again, the takeaway from here is that it's never too late to catch up. And delayed doesn't mean denied, really. Your child can still be protected. And this now takes me to um the second last portion of our conversation today, which is when should parents be concerned uh with regard to vaccine-associated side effects. Typically fever. Fever is extremely common. Uh, I think, particularly in the first couple of months when your baby has an intense schedule where they get something almost every month, most of the babies do get a fever. And a fever after vaccination, yes, can be worrying, but it's actually a normal sign that your child's immune system is responding appropriately to the vaccine. These vaccines are typically, vaccines are typically combined and they mobilize the immune system to an extent that uh the inflammatory response would typically trigger a mild fever. Now we say mild fever, mild fever would say would refer to something in the range of uh 38 degrees Celsius, could be slightly more, and this fever typically lasts for two to three days. It gets better after the first 24 hours, but can last a bit longer. The other common thing is fussiness. You know, your baby would be fussy, they are fussy, they are restless, um, they don't feed as as well as they usually do. And the other thing is that there's usually a swelling, uh, inflammation, a redness, and pain around the injection site. So those three things are very typical and very frequent: mild fever, fastiness, and swelling at the injection site. And these would typically go away, like I said, within at least the most uncomfortable part within 48 to 72 hours. But I've also seen babies that are sick the entire week. The point to note there is that as long as the symptoms and the side effects get gradually better, then you're okay to wait them out and appropriately use uh pain medication. So a paracetamol, we typically recommend it to be given regularly, particularly the first 24 to 48 hours when the symptoms are very uncomfortable and very intense. However, there are times when parents should actually seek medical advice. So you should definitely seek help if there's any form of allergic reaction, any uh swelling, if the body, the whole body is swollen, if there's any breathing difficulty. And these would typically happen immediately after the vaccine. So you're probably still in the clinic or at the hospital. So severe allergic reactions do occur. They're very rare, but they can occur. The other element to note is if the fever is very high, if your child maintains a temperature above 39 degrees, so high grade fever, and it's just sustained. Um, and that usually is not something that you should ignore. You should, especially in younger babies, if your baby is still within the first six months of life, uh, you definitely need to get that checked out. The other element is that if the fever lasts more than two to three days, um and it's not showing signs of slowing down. So you vaccinate, you had your baby vaccinated three days ago. This is day four, and the fever still looks the same as it was on day one. So even if it's low grade, I would still encourage that you get a medical opinion and get a healthcare provider to look at your baby. Then there's other symptoms that really show severity. If your baby is unusually drowsy, they are sleepy, more sleepy than unusual, they are unresponsive, or they are on the other spectrum of crying inconsolably, that they are uh crying non-stop for hours and hours and hours. Um, inconsolable crying is not a good sign. Uh, that would be something that requires help from a healthcare provider for them to look at your baby and make sure that everything is okay. So, what should you do at home? Um, you should mainly make sure that your child is well hydrated. You know, if they breastfeed, let's say the first day they might be very fussy and very irritated and very uncomfortable. But at least they should be able to feed a reasonable amount. And we usually say, you know, look at your nappies, are your baby's nappies, are they passing urine more or less the same amount as usual? Then, you know, if they are hot and they are warm and you've given prostitamo, but they are still warm, dress them lightly. You know, make sure that they are not over-dressed or overcovered. Um, and as I mentioned before, do not hesitate to use a parastitamol every six hours at the appropriate dose given by your healthcare provider. So um before I go on to some of your questions, I would like to wrap up this session on uh the second conversation around vaccines with just some key reminders. Mild illness does not usually prevent vaccination. If your baby missed vaccines, this can be safely caught up, and there's no need to start over. Fever after vaccines is common, and it's important to know when to be concerned and when the need is there to seek help. So parenting comes with many decisions, and it's okay to have questions. The most important thing is to stay informed and work closely with a trusted healthcare provider. And I encourage you to stay informed, to stay calm, and to keep giving your children the healthiest start possible.

SPEAKER_00 21:52

First question from Oscar Fordy and living in Kigali. My toddler gets fever quite often, and every time it happens, we panic. What's considered a normal frequency and when is it serious?

SPEAKER_01 22:04

So indeed, fever is a frequent and very common symptom, but it's also a very nanspecific symptom. And what I mean by this is uh when your baby gets a cold or a cough, these frequent viral infections that most children get six to eight of them, six to eight episodes of this per year. And if you think about it, if each episode lasts about two weeks, they are frequently sick, and most of these episodes will come with a fever. So fever in itself is uh nine-specific, it's just a trigger, it's an alert. And you usually if fever is low grade, low grade meaning is below 39 degrees Celsius, uh response to fever medication, you give a paracetamol and the fever actually goes away. And your child has very clear symptoms of a viral infection, of a flu, of a cough, and they're generally well. They're able to feed, they're able to hydrate, they have reasonably good energy levels, that's probably not a fever that you should worry too much about. However, even if it's low grade, if it persists for longer than 48 to 72 hours, you generally should get it checked out. Because even if uh your child clearly has a viral episode, virus symptoms, flu and cough that can be ignored, there's always a chance that they might have something more, they might have malaria, they might have something underlying, even though they are not getting a very high grade fever. So um those are just general guides that I would give in terms of when you should be concerned, so how high it is, how long it lasts, and what are the additional symptoms that your child has, and how is that general state?

SPEAKER_00 24:13

Last question from Nina 35, also from Kigali. My mother-in-law is very involved with a baby, which I appreciate, but sometimes she insists on doing things her way: feeding, routines, and even discipline. It creates tension because I want to raise my child differently. How do you manage this without conflict?

SPEAKER_01 24:32

That's quite typical, and that's especially in our African setup, you know, we have parents that usually want to be involved. In fact, if I take an example of Rwanda, it's almost like uh a cultural rule that when a mother gives birth, if they are blessed to have a parent either on their side, their own parent or their spouse's mom, they typically get involved. There's even a terminology for that, and mothers will come and stay for prolonged periods helping the new mother who was given birth to take care of the baby. So, in and in itself, it's actually a good thing. It's it's family support. However, understandably, um your parents or your mother-in-law might have different understanding, different beliefs, the way they do things that differs from how you want to do them, how you want to raise your baby, how you want to feed them. So, again, my simple advice would be that have a conversation. You know, most people uh build up resentment and they don't really voice what they feel and what they're concerned about. However, I I noticed and I realized that when people actually discuss these things openly and you speak to your mother or your mother-in-law and tell them, look, I appreciate that you're helping me, I appreciate that you're here, you're taking off a lot of stress from me from taking care of the baby, and this is really appreciated. However, there's one or two things that I disagree with and I would like to discuss, and these are the following. The reason I disagree with them is because of one, two, three. Either there's recent evidence, there's recent data and information that actually recommends that things are done differently. So I would prefer to do them this and this certain way, as opposed to how you do them. These are conversations that can be had, and uh I think most good people will be reasonable, and uh that should help hopefully help to resolve the tension and the conflict. Thank you for listening to Healthy Beginnings. If you have any questions you'd like answered in the next episode, you can submit them to our email, healthybeginningspodcast at gmail.com. You can also follow us on all social media platforms. You can find us on YouTube as well as the audio platforms of your choice. See you next week.

SPEAKER_00 27:26

This podcast is for general informational and educational purposes only. Do not make health decisions without consulting your doctor. This podcast is brought to you by LF Media, home of great African podcasts.