Everything you need to know about ticks and mosquitoes: protective measures, diseases, and treatments
Mosquitoes and ticks return with the warm weather, turning walks in nature or evenings on the terrace into a real challenge. Beyond the discomfort caused by bites and stings, these insects can transmit serious diseases. Every year, health authorities draw attention to the risks associated with these insects, especially during the spring and summer periods, when their populations reach high levels. That is why it is essential to know what real dangers they can bring, how to recognize the symptoms of possible infections and how they can be treated, but also what prevention methods we have at our disposal to avoid complications.
Both mosquitoes and ticks are hematophagous insects. They ingest microorganisms responsible for diseases during a blood meal from an infected host (human or animal), which they then transmit to a new host after the pathogen replicates. Once the insects have become infectious, they can transmit the pathogen for the rest of their lives during every new bite/sting. (*** (National Institute of Public Health), 2024)
General information about ticks
Ticks (Ixodidae) are ectoparasites with a hematophagous and intermittent feeding mode, thus being important vectors for many pathogens in both humans and mammals, reptiles, and birds. (Ali, Mulenga, & Vaz, 2020) As temperatures rise, ticks become active.
Several species have been identified in our country. Of the four types of ticks located in Romania, according to the European Centre for Disease Control and Prevention (ECDC) (***, Tick maps, 2023), the most frequently encountered is Ixodes ricinus (the deer tick) (***, 2018).
They can be found in forests, meadow and pasture areas, but also in semi-desert regions with dry climates or inside homes (the Rhipicephalus sanguineus species). (***, Prevention and control of tick-borne diseases in Europe, 2015)
The life cycle of ticks includes four developmental stages: egg, larva, nymph, adult tick. In the last three stages, they can bite and transmit diseases. The risk is lower when the tick is detected and removed immediately. Thick snow can facilitate survival through the winter, as they can adapt to temperatures below 0°C, and rising temperatures help accelerate their life cycle, which is otherwise completed in 2-3 years. (***, Small bites, big problems: tick-borne diseases in Europe, 2014)
Diseases caused by tick bites – symptoms and treatment
In Europe, the 4 diseases that can be caused to humans by tick bites are Lyme disease, tick-borne encephalitis (a serious infection of the brain and spinal cord), relapsing fever, and Crimean-Congo hemorrhagic fever. Allergic individuals may experience pain at the site of the bite, swelling, a burning sensation, and sometimes even breathing difficulties. (***, Prevention and control of tick-borne diseases in Europe, 2015)
Ixodes ricinus is responsible for causing the first three diseases, being frequently observed in deciduous and mixed forests, requiring a humidity of at least 80% for replication, whereas in the case of Crimean-Congo hemorrhagic fever, Hyalomma marginatum is the culprit, being present in southern and eastern Europe. (***, Small bites, big problems: tick-borne diseases in Europe, 2014)
| Lyme disease (Borreliosis) | Tick-borne encephalitis | Relapsing fever | Crimean-Congo hemorrhagic fever | |
| Symptoms | - Reddish circular skin rash (around the bite, in 80-90% of cases), sometimes associated with a burning or stinging sensation - Fever, fatigue, headache - If untreated, it causes infections of the heart, liver, lungs, eyes, joints, and nervous system |
- Viremic phase (5 days): fever, fatigue, headache and muscle pain, nausea - Asymptomatic interval (7 days on average, can range between 1-33 days) - Advanced phase presents symptoms similar to meningitis and requires hospitalization |
- Repeated episodes of fever over 39-40°C, headaches (lasting between 3 and 6 days), muscle and joint pain, nausea, intense asthenia - Splenomegaly, hepatomegaly, associated with jaundice, increased heart rate and blood pressure - Shorter and milder relapses may occur after the first fever episode |
- Sudden onset of fever, headache, muscle pain, joint pain, abdominal pain, and vomiting - Hemorrhagic manifestations (petechiae, ecchymoses) that appear on the skin and mucous membranes (nose, gastrointestinal system, uterus, urinary and respiratory tracts), including at venipuncture sites - Possible necrotic hepatitis |
| Incubation period | Up to 30 days after the bite | 7 days on average (but can occur between 3-28 days) after the bite | 3-18 days after the bite | 3-7 days (can range between 1-13 days) after the bite |
| Treatment | - Antibiotic administration - Complications may occur after the end of treatment: post-treatment Lyme disease syndrome (asthenia, severe muscle and headaches), arthritis and joint pain, memory problems, numbness, tingling and stinging in the limbs and face, stress, anxiety, and depression (due to the persistence of symptoms) |
- No treatment - Pre-vaccination and protective measures are very important |
- Antibiotic administration (tetracycline or doxycycline). If tetracycline is contraindicated, a macrolide may be prescribed. - Treatment can cause a Jarisch-Herxheimer reaction (acute febrile reaction) within two hours of treatment. |
- Supportive care, administration of platelets, fresh frozen plasma, and erythrocyte preparations - Oral ribavirin has been successful in some cases - Taking protective measures is very important |
(***, Prevention and control of tick-borne diseases in Europe, 2015)
What to do in case of tick bites?
Since it is not painful, the bite often goes unnoticed. Therefore, a thorough check is important after being in places where ticks may exist. The entire body should be checked, paying greater attention to the underarm, groin, navel, leg, neck, and head areas (often, in children, they have been detected on the scalp, at the base of the hair – a magnifying glass is necessary). The bite looks like a small, dark swelling with a crust that cannot be removed by combing. (***, Prevention and control of tick-borne diseases in Europe, 2015)
If you notice a tick in the skin, it is important to act quickly and correctly: disinfect the area with alcohol and use blunt-tipped tweezers (no teeth) to carefully grasp the tick's body as close to the skin as possible, pulling gently in one motion without yanking or twisting. Do not grasp it by the head because there is a risk that it will break and remain fixed in the skin. Do not apply heat or any other substance because the tick may discharge its stomach contents, facilitating the transmission of diseases.
Wrap it in a tissue and throw it in the toilet, then wash the area with soap and water and apply an antiseptic or disinfectant solution (sanitary alcohol, povidone iodine). (***, Borreliosis (Lyme disease), 2014)
If after a few days you notice that the lesion is not healing or symptoms mentioned in the table above appear, even after a month from the bite, consult a doctor, providing all necessary information regarding it.
How do we prevent tick bites?
Avoid places with thick and tall grass, dress appropriately (light-colored clothing that covers the skin – long sleeves, long pants, socks over pants, and sports shoes/boots without holes) and use tick repellents with DEET (diethyl toluamide) or based on natural oils on areas that may come into contact with tick-infested zones (***, Leaflet for travellers on ticks, tickborne diseases and preventive measure, 2015), such as Klinodiol anti-mosquito and tick spray.
Another useful prevention option is vaccination, with the mention that this method only protects against tick-borne encephalitis. It is recommended for people who travel and stay for a longer period in a place where this disease is endemic for more than three weeks. Multiple doses are needed for high efficacy.
It is important to reduce high vegetation by mowing the grass or lawn, remove piles of dead leaves and fallen branches by burning them, and seal holes and cracks in houses. Periodically deparasitize pets and domestic animals.
Last but not least, use an insecticide for tick control, such as Aptanex forte (which is also effective against cockroaches, fleas, bedbugs, flies, ants, spiders, and other flying and crawling insects).
General information about mosquitoes
Mosquitoes (Culicidae) are dipterous insects present on all continents except Antarctica. There are three genera of clinical significance responsible for biting humans: Anopheles, Culex, and Aedes. (Mosquito Bites, 2021)
They are usually found near places with standing water because they are suitable for completing their life cycle. Reproduction occurs through eggs with complete metamorphosis, egg→larva→nymph (pupa)→adult, and incomplete metamorphosis, egg→larva→adult. Mosquitoes lay their eggs on the surface of the water. The male consumes plant juice and nectar, and the female feeds on the blood of mammals, birds, and humans because it needs food for egg production. (Walrond, 2007)
The European Centre for Disease Prevention and Control (ECDC) has warned about an increased risk of mosquito-borne diseases in Europe (***, Increasing risk of mosquito-borne diseases in EU/EEA following spread of Aedes species, 2023). Global warming caused by climate change favors the emergence of certain mosquito species responsible for the spread of malaria and dengue fever in Europe. "Climate change-related droughts and floods can lead to greater virus transmission, with stored water providing additional breeding sites for mosquitoes." – Professor Rachel Lowe (Barcelona Supercomputing Center) (Horton, 2024)
Diseases caused by mosquito bites – symptoms and treatment
In Europe, the 4 diseases that can be caused to humans by mosquito bites are West Nile virus infection, Zika, Dengue (Dengue fever), and Chikungunya (Chikungunya fever). The West Nile virus is spread by Culex mosquitoes, while the other infections are caused by Aedes species. Malaria and yellow fever are much more common in the tropical areas of the world, being transmitted by the Anopheles mosquito in the first case and by the Aedes aegypti mosquito in the second. (Mosquito Bites, 2021)
The reaction that occurs after a bite is largely caused by toxins in the mosquito's saliva that enter the human bloodstream. These have vasodilatory, anticoagulant, and antiplatelet properties. The result is the appearance of a pruritic papule. The mosquito becomes a transmission vector for the virus after feeding on the blood of an infected animal or person, which it then transmits through its saliva. (Mosquito Bites, 2021)
| West Nile virus infection 1, 2 | Zika virus infection 3, 4 | Dengue virus infection (Dengue fever) 5, 6 | Chikungunya virus infection (Chikungunya fever) 7, 8 | |
| Symptoms | - No symptoms or: - Fever - Headaches, muscle and joint pain - Nausea and vomiting - Swollen lymph nodes - Diarrhea - Pain behind the eyes - Sore throat - Skin rash (usually on the chest and back) - Requiring urgent medical check and hospitalization: high fever over 39.5°C, severe headache, stiff neck, muscle weakness, confusion, disorientation, seizures, paralysis - Serious complications: meningitis and encephalitis - In the worst case: coma |
- No symptoms or: - Mild fever - Headache, joint and muscle pain - Skin rashes - Conjunctivitis - If a pregnant person is infected: congenital anomalies, including microcephaly or fetal death |
- No symptoms or: - Mild symptoms (cold-like) or severe: high fever (40°C), headache, muscle and joint pain, nausea, vomiting, pain behind the eyes, swollen glands, skin rashes - Severe form (dengue hemorrhagic fever) can be lethal and requires hospitalization |
- High fever with sudden onset - Joint pain - Headaches and muscle pain - Skin rashes - Fatigue - Nausea - Red eyes - Swelling of the joints - The disease is self-limiting, but joint pain can persist for a longer period - Complications are rare, but if they occur, they include eye, heart, and nerve damage. |
| Incubation period | 2-6 days (sometimes up to 14 days) after the bite | 3-12 days after the bite. It is also transmitted sexually. | 4-10 days after the bite | 2-7 days after the bite |
| Treatment | - Symptomatic (avoid anti-inflammatories that may increase the risk of bleeding until Dengue virus infection is excluded) - In case of severe neurological symptoms, these will be treated at the hospital through the administration of anticonvulsants, corticosteroids, intravenous fluids, oxygen |
- Symptomatic (avoid anti-inflammatories that may increase the risk of bleeding until Dengue virus infection is excluded) - Rest and hydration |
- Symptomatic (avoid anti-inflammatories that may increase the risk of bleeding) and hydration - In severe cases, hospitalization with intravenous treatment and blood transfusions is necessary |
- Symptomatic (avoid anti-inflammatories that may increase the risk of bleeding until Dengue virus infection is excluded) |
1 (Balzer, 2023)
2 (***, West Nile Virus, 2023)
3 (Poland, Ovsyannikova, & Kennedy, 2019)
4 (***, Treatment of Zika, 2024)
5 (***, Dengue fever - symptoms&causes, 2022)
6 (***, Dengue fever - Diagnosis & treatment, 2022)
7 (Pritish K. Tosh, 2023)
8 (Symptoms, Diagnosis, & Treatment | Chikungunya Virus , 2024)
What should we do in case of mosquito bites?
There are certain factors that can make mosquito bites more frequent: dark clothing, perfume, body temperature, blood type, visiting regions with active diseases transmitted by them, and time spent near standing water. (***, Mosquito Bites, 2021)
In case of a mosquito bite, it is recommended to wash the area with soap and water, and apply an ice pack for a few minutes to reduce swelling and itching. You can subsequently apply an antihistamine cream/gel, aloe vera, chamomile tea, or honey, and in case of more intense allergic reactions, an oral antihistamine can be administered. Scratching should be avoided as it can lead to infection of the area. (***, Mosquito Bites, 2021) In the case of more severe symptoms (presented in the table above), medical consultation is advised.
How can we prevent mosquito bites?
It is advisable to eliminate any source of stagnant water around the home and remove household waste. Windows and doors of homes should have mosquito nets installed. Also, use mosquito repellent products inside the home (electric devices with liquid or capsules, coils, candles, or aromatic oils based on lavender, chrysanthemum oil, eucalyptus).
Another method that can keep mosquitoes at bay is using a fan. They are attracted to carbon dioxide and other chemicals that we emit when we breathe. According to Melania Rose, a pest specialist at Nationwide Pest Control, fans can make it harder for mosquitoes to detect these chemicals in the air, making them less capable of finding their target. (Slack, 2022)
Avoid or limit trips to areas with lots of vegetation, high humidity (forests, parks, standing water, etc.) and those with a high risk of infection. Dress appropriately, with thicker long-sleeved shirts, long pants, and socks, and use mosquito repellents with DEET (diethyltoluamide) or based on natural oils, such as Klinodiol anti-mosquito spray. For children, you can use anti-mosquito patches or an anti-mosquito bracelet (for those older than three years). Treat tents with repellents as well if you are sleeping outdoors.
Therefore, the prevention of diseases transmitted by mosquitoes and ticks can be primarily achieved through the use of a repellent. It should not be applied near the eyes and mouth, over sunburns, cuts, wounds, or skin rashes, nor under clothing. Avoid inhaling it and do not apply it near flames. Always check the instructions, method of use, and contraindications mentioned on the product label. Once you enter the house, wash the areas where you applied the repellent with soap and water.
If you follow all these recommendations, you will be able to enjoy your time spent outdoors peacefully, without worrying about mosquitoes and ticks.
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