Feeling a bit feverish? Stay cool

Winter is on its way bringing colder and breezy days, which can be an extra challenge for our immune system, increasing the chances of infection, such as a simple cold or the flu. Luckily, our bodies have quite intricate and smart mechanisms to help us getting through, a good example being fever (when the human’s body goes above its normal temperature of 36-37C), an effective response of the immune system to combat infections. Thus, the next time you are feeling “under the weather” and a bit feverish, you may want to think twice before quickly reaching to the medicine cabinet. 

The fever as a friend?

Most illness-causing microbes such as bacteria and viruses thrive at the body’s normal temperature, but do not replicate well if the body temperature raises. A fever kicks the immune system and in fact letting it run its course may reduce the length and severity of a cold or the flu, and even boost the immune system preventing future infections.

Therefore, as long as the fever is mild and not part of a serious condition, there are good reasons for not suppressing it unnecessarily. This view is gaining increasing support amongst the medical community.

However, it is important to consider the cause of fever, particularly in children, pregnant women, travellers and the elderly. If a person is confident that a dangerous disease is unlikely, then the best approach is to manage the fever so it remains at acceptable levels (below 39C). See section below on how to manage your fever.

How does the fever kick the immune system?

A febrile response is well known to be associated with fighting infections and, regardless of its energetic demand on the body, it has been selected by evolution through time. Thus, the fever must have an important adaptive role in stimulating the immune system.

Studies have shown that higher temperatures affect the composition and fluidity of cell membranes, therefore compromising entry of pathogens inside the cell. Interestingly, another study published earlier this year has demonstrated an additional mechanism, by which fever alters immune cells. A temperature increase can alter surface proteins on immune cells called lymphocytes, making it easier for them to travel through the body and effectively reach sites of infection.

How to manage a fever

• Take your temperature regularly with a thermometer
• Drink plenty of fluids to prevent dehydration
• Give your body a chance to rest, and know when to stop. This is very important, particularly in nowadays hectic society. If you do not find space in your life for wellness, eventually you may be forced to find space for illness.
• Consider immune boosting supplements such as vitamin C, zinc, echinacea and propolis.

However, if your body temperature gets too high, try first sweating it out with yarrow (latin name: Achillea millefolium), one of the best herbs for fever. Yarrow is what we call a cooling diaphoretic, which means that it opens your pores inducing perspiration. This will help controlling and reducing your body temperature and at the same time release toxins. Take yarrow as a hot infusion/tea (1 to 2 teaspoons of dried yarrow in 1 cup of boiling water, steep for 15 minutes, strain and drink warm; drink 3 times daily ideally while covered in bed).


And this is how fever can be your best friend helping to keep infections at bay. Next time you are feeling only a bit hot, you may want to control the urge to quickly bring it down. Cool isn’t it?

References

Lin, C. D. et al. Fever Promotes T Lymphocyte Trafficking via a Thermal Sensory Pathway Involving Heat Shock Protein 90 and α4 Integrins. Immunity (2019). doi:10.1016/j.immuni.2018.11.013

Mace, T. A. et al. Differentiation of CD8 + T cells into effector cells is enhanced by physiological range hyperthermia . J. Leukoc. Biol. (2011). doi:10.1189/jlb.0511229

Mills, S. and Bone K. Principles and Practice of Phytotherapy, Modern Herbal Medicine (2008). Churchill Livingstone.
Papatriantafyllou, M. Heating up T cell activation. Nat. Rev. Immunol. (2012). doi:10.1038/nri3146

Plaza, J. J. G., Hulak, N., Zhumadilov, Z. & Akilzhanova, A. Fever as an important resource for infectious diseases research. Intractable and Rare Diseases Research (2016). doi:10.5582/irdr.2016.01009