Conjunctivitis in babies and children: nursery, school, contagion

The phone rings in mid-morning, and it is the nursery: ‘Your child has a red, sticky eye, please come and pick them up.’ For many parents it is a familiar scene, and not by chance. A British study estimates that every year one school-age child in eight has an episode of infectious conjunctivitis¹.

Behind that phone call lie three questions: is it a virus or bacteria? Is an antibiotic eye drop needed? When can they go back to class? On the first two, the studies have fairly clear answers. On the third, far less so.

In this article

1. Why children get it so often
2. Conjunctivitis in children: bacteria or virus?
3. Antibiotics or not: the studies in children
4. Nursery and school: at home or in class?
5. Newborn babies: a separate case
6. Frequently asked questions
7. Sources

Why children get it so often

The most solid figures come from family medicine. In 2001, in the Netherlands, all the contacts between 195 family doctors and their 375,899 patients were analysed over a full year: there were 5,213 episodes of infectious conjunctivitis, about 14 per 1,000 people a year. In children up to one year of age, however, they exceeded 80 per 1,000; after the age of four they fell below 12². A 2008 review estimates that bacterial conjunctivitis alone accounts for about 1% of all general practice consultations⁷.

How these infections pass from one person to another, and why hands matter so much, we explain in our article on how conjunctivitis is transmitted.

Conjunctivitis in children: bacteria or virus?

Unlike what happens in adults, in children bacterial conjunctivitis is the most common^3,4. A 2023 paediatric review describes the three main forms as follows³:

• bacterial: thick, yellowish discharge, stuck eyelids;
• viral, caused mainly by adenovirus: burning, a feeling of grit in the eyes, watery tears;
• allergic, largely seasonal: itching in both eyes and watery discharge.

In practice, however, telling bacteria from a virus just by looking at the eye is difficult, and reviews have stressed this for years⁷. The differences between the three forms are described in our article on viral, bacterial or allergic conjunctivitis.

Antibiotics or not: the studies in children

A more recent Finnish study, carried out in Oulu between 2014 and 2020, divided 88 children aged between 6 months and 7 years into three groups: antibiotic eye drop, placebo eye drop, no eye drop. With the antibiotic the symptoms disappeared on average in 3.8 days, with no eye drop in 5.7: about two days fewer. Even the placebo eye drop, curiously, shortened the time compared with no treatment. The same authors then pooled four studies with 584 children: with antibiotics, the proportion of children still with symptoms between the third and the sixth day was lower than with the placebo⁵.

The picture is consistent with the 2023 Cochrane review, which examined 21 studies, not only in children: antibiotic eye drops speed up resolution modestly, with evidence of moderate certainty⁶. A paediatric review suggests deciding case by case, because the antibiotic can shorten the symptoms but is not free of risks³; another notes that ‘delayed’ prescribing, to be used only if the symptoms do not improve, controls symptoms in a similar way to immediate prescribing⁴. In practice, however, antibiotics are used a great deal: in the Dutch data a local treatment for the eye was prescribed in 87% of episodes, and in 80% of cases it was an antibiotic².

Nursery and school: at home or in class?

Here the evidence is scarce, and the rules vary. A study of the 60 nurseries in a region of Israel found that 83% sent home children with eye discharge or conjunctivitis, and almost half asked for a medical certificate for their return; but about half of the nurseries decided on the basis of ‘common sense’ and personal feelings, not official guidance⁸. It is a single country and a twenty-year-old study; but in Europe too the rules change from one country to another, and often from one school to another. Ask the paediatrician and the school how it works where you live.

Then there is a knot that the studies have not untied. A 2008 review observes that the antibiotic is often prescribed also because it allows children to return to nursery or school sooner, but that the effect of prescribing fewer antibiotics on the transmission of germs remains to be clarified⁷. The Cochrane review too stresses that a faster recovery matters for returning to school or work⁶. In the meantime, the measure recommended by the reviews is hygiene, starting with frequent hand washing⁴.

Newborn babies: a separate case

In the first weeks of life conjunctivitis, also called ophthalmia neonatorum, has different causes and risks. At a children’s hospital in Dublin, between 2013 and 2018, 54 cases were studied: the most frequent cause was chlamydia (20.4%), followed by Staphylococcus aureus (18.5%) and Haemophilus influenzae (14.8%). Half of the babies were admitted to hospital and almost one in two received intravenous antibiotics⁹. A 2022 review notes that some of these infections can cause complications throughout the body, and that the prophylaxis given at birth in some countries does not protect against all the causes¹⁰. For this reason the reviews recommend that conjunctivitis in a newborn baby should always be assessed⁴.

Frequently asked questions

Can a child with conjunctivitis go to nursery?

It depends on the rules of the place, which vary greatly between countries and between settings⁸. Studies have not clarified how much keeping children at home reduces infections⁷. Washing hands often remains the recommended measure for reducing transmission⁴.

Does conjunctivitis in children clear up on its own?

In most cases it does. In the British study of 326 children, 83% of those treated with a placebo were better within seven days¹.

Why does the paediatrician sometimes not prescribe the antibiotic eye drop?

Because the benefit is modest: a few days fewer of symptoms, according to the studies^1,5,6. One possibility that has been studied is ‘delayed’ prescribing, to be used only if the symptoms do not improve⁴; and the antibiotic, like any medicine, is not free of risks³.

Is conjunctivitis in a newborn baby dangerous?

It can be, more than in older children: some of the causes can cause complications throughout the body¹⁰. In the Dublin study the most frequent cause was chlamydia, and half of the babies were admitted to hospital⁹.

Conjunctivitis is one of the most common complaints of childhood and, in most cases, clears up on its own within a week¹. The studies say that the antibiotic shortens the time a little, that the rules on nursery and school are more a local habit than the fruit of evidence, and that one exception must always be taken seriously: that of the newborn baby.