SENTINEL project

Information for general public

The SENTINEL Project is a regional public health initiative focused on early detection and surveillance of infectious diseases, especially those spread by vectors like ticks. It aims to protect communities by monitoring disease threats and sharing alerts across Balkan countries. This is increasingly important as tick-borne diseases become a growing concern in our region. (For example, a dangerous tick-borne virus, Crimean-Congo Hemorrhagic Fever, re-emerged in North Macedonia in 2023 after over 50 years, with cases occurring near the Serbian border, highlighting the need for vigilance.)

Tick-Borne Diseases in the Balkans: Several illnesses can be transmitted by ticks in the Balkans.

Key diseases include:

  • Crimean-Congo Hemorrhagic Fever (CCHF): A rare but severe viral hemorrhagic fever that can cause high fever, bleeding, and organ failure. CCHF has recently reappeared in North Macedonia, showing that the threat is real. It is spread by Hyalomma ticks and can also transmit through contact with infected animal blood or fluids.

  • Lyme Disease: A common bacterial infection (also known as Lyme borreliosis) spread by Ixodes ticks. Early symptoms include fever, fatigue, and often a characteristic “bull’s-eye” skin rash at the bite site. If untreated, Lyme disease can lead to arthritis, nerve problems, or heart issues, but it is treatable with antibiotics when caught early.

  • Tick-Borne Encephalitis (TBE): A viral infection of the central nervous system. TBE can cause meningitis or encephalitis (brain inflammation). Early symptoms are flu-like (fever, aches), which can progress to severe headache, stiff neck, and confusion. A vaccine is available for TBE, and it is recommended for those in or traveling to endemic areas. (TBE is present in parts of Europe, though it has not been commonly reported in North Macedonia or Serbia to date.)

  • Other Tick-Borne Diseases: Ticks in this region can also carry other illnesses, such as Mediterranean spotted fever (a rickettsial infection causing fever and rash), tularemia (which can cause fever and swollen glands), babesiosis (a malaria-like parasitic infection causing fever and blood cell damage), and anaplasmosis/ehrlichiosis (bacterial infections causing fever and low blood counts). These diseases are less common but can occur; many are treatable if diagnosed promptly.

Preventive Measures (Protect Yourself from Ticks):

  • Use Repellents: Apply insect repellent (such as DEET or picaridin) on exposed skin and clothing to deter ticks.

  • Wear Protective Clothing: When in wooded or grassy areas, wear long sleeves, long pants tucked into socks, closed shoes, and a hat. Light-colored clothing is advisable so ticks are easier to spot.

  • Stay on Trails: Avoid brushing against tall grass or bushes. Walk in the center of trails when hiking; ticks are often lurking in dense vegetation.

  • After Outdoor Activities: Immediately after being in nature, check your body (and your children/pets) for ticks. Pay attention to areas like the scalp, behind ears, under arms, waist, and behind knees. Showering within two hours of coming indoors can help wash off any unattached ticks.

  • Home and Pets: Keep grass and bushes trimmed in your yard to reduce tick habitat. Use veterinarian-recommended tick control products on pets to avoid ticks coming home on animals.

What to Do After a Tick Bite:

  1. Remove the Tick Safely: Do not squeeze, twist, or crush the tick. Do not try to burn it or apply petroleum jelly or chemicals. Instead, use clean fine-tipped tweezers to grasp the tick as close to the skin as possible and pull it straight out gently and steadily. (If you are unsure or unable to do it, seek help at the nearest medical center.)

  2. Disinfect the Area: Once the tick is out, clean the bite area with rubbing alcohol or soap and water. Wash your hands thoroughly with soap and water as well.

  3. Save the Tick (Optional): If possible, save the tick in a clean plastic container or zip-lock bag (you can place a damp piece of paper towel inside to keep it moist). Mark the date of the bite on the container. In some locations, you can bring the tick to a laboratory for testing (for example, the Clinic for Infectious Diseases in Skopje or the Pasteur Institute in Novi Sad can analyze ticks for pathogens).

  4. Monitor Your Health: Keep an eye on the bite site and your health for the next few days to weeks. It is normal for a small red bump to form at the bite. However, if you notice a spreading rash, or develop flu-like symptoms such as fever, headache, muscle/joint aches, or any unusual symptoms, contact a healthcare provider. Early diagnosis and treatment are crucial if a tick-borne disease develops.

Signs and Symptoms to Watch For: After a tick bite, be alert for symptoms of tick-borne illnesses. Key signs include:

  • Flu-like symptoms: Fever, chills, fatigue, headaches, and body aches can be early signs of many tick-borne diseases (Lyme, TBE, anaplasmosis, etc.).

  • Skin changes: A red expanding rash (often ring-shaped like a bull’s-eye) at the bite area is a hallmark of Lyme disease. Also, a black scab at the site could suggest tularemia (ulceroglandular form).

  • Neurological symptoms: Severe headache, stiff neck, sensitivity to light, dizziness, or confusion could indicate tick-borne encephalitis or advanced Lyme disease affecting the nervous system. These symptoms require immediate medical care.

  • Bleeding or bruising: Unusual bleeding (for example, frequent nosebleeds or bleeding gums), appearance of numerous small bruises or red spots on the skin, along with fever, could be signs of CCHF – this is a medical emergency.

  • General malaise: Many tick infections cause a general unwell feeling. If you feel very unwell after a tick bite, trust your instincts and see a doctor, mentioning your tick exposure.

Always inform the doctor about the tick bite if you become ill. Early recognition of symptoms and prompt treatment can greatly improve outcomes for diseases like Lyme (which is cured with antibiotics) and can be life-saving in serious infections like CCHF.

Information for professionals

Introduction and Overview: Tick-borne diseases are an emerging challenge in the Balkans, and healthcare professionals play a critical role in surveillance, diagnosis, and management. The SENTINEL Project (with the Balkan Association for Vector-Borne Diseases, BAVBD) facilitates cross-border collaboration and information-sharing to improve early detection of diseases like CCHF, Lyme borreliosis, and others. Recent events — such as the re-emergence of CCHF in North Macedonia in 2023 (after decades of absence) and a 2024 case less than 20 km from the Serbian border — underscore the importance of vigilance and preparedness in our region. Below is a summary of key tick-borne diseases in the Balkans, along with diagnostic and management guidance and reporting recommendations for medical staff.

Crimean-Congo Hemorrhagic Fever (CCHF)

Etiology: CCHF is caused by a Nairovirus (Bunyaviridae family) primarily transmitted by Hyalomma ticks. It can also spread via contact with blood or bodily fluids of infected animals or patients (human-to-human transmission is possible, requiring strict infection control).

  • Diagnosis: Suspect CCHF in patients with acute febrile illness, bleeding tendencies, and a history of tick bite or exposure to livestock in endemic areas. Laboratory confirmation is made by detecting the virus (RT-PCR) or serology (IgM and IgG antibodies) – ideally performed in high biosafety laboratories. Liver enzymes, coagulation profiles, and blood counts are important for patient monitoring (common findings include thrombocytopenia, elevated liver enzymes, and prolonged clotting times).

  • Reporting: CCHF is immediately notifiable. Follow national guidelines to report suspected or confirmed cases to public health authorities without delay (due to its outbreak potential). Early notification can prompt contact tracing and prophylactic measures for contacts. International reporting (e.g. to WHO) may be warranted if cases indicate wider spread.

  • Clinical Management: There is no specific antiviral cure with confirmed efficacy, but ribavirin has been used in some cases (best if started early) based on observational data. The mainstay is intensive supportive care: management of fluid and electrolyte balance, organ support as needed, and careful blood product transfusion if bleeding is severe. Patients should be isolated following strict barrier nursing protocols to prevent nosocomial transmission. Mortality can be high (10–40%), so aggressive supportive treatment and ICU care are often required.

Lyme Disease (Lyme Borreliosis)

Etiology: Lyme disease is caused by pathogenic members of Borrelia burgdorferi sensu lato complex and transmitted by Ixodid ticks (e.g. Ixodes ricinus in Europe). It is the most frequent tick-borne disease in temperate Europe.

  • Diagnosis: Early localized Lyme disease is diagnosed clinically by the presence of erythema migrans (the characteristic expanding rash) in a patient with tick exposure. Serological tests (ELISA screening, confirmed by Western blot) are most useful in later stages; they may be negative in the first weeks of infection. Be aware of possible false positives; interpret tests in the context of symptoms. For Lyme neuroborreliosis, analysis of cerebrospinal fluid for antibodies may be indicated.

  • Reporting: Lyme disease is a notifiable condition in many countries, though often with less urgency than CCHF. Clinicians should report cases according to local public health requirements (usually within weekly or monthly surveillance reports) to help track incidence.

  • Clinical Management: Prompt antibiotic therapy is very effective. First-line treatment for early Lyme is doxycycline or amoxicillin, which usually leads to full recovery. There is no approved vaccine for Lyme in the Balkans currently, so prevention (tick bite avoidance) is crucial.

Tick-Borne Encephalitis (TBE)

Etiology: TBE is caused by the tick-borne encephalitis virus (TBEV, a flavivirus). It is transmitted by Ixodes ticks and can also be contracted by consuming unpasteurized dairy products from infected animals. The disease is endemic in parts of Central, Eastern, and Northern Europe; parts of the Balkans have ecological conditions for TBE vectors, though North Macedonia is currently non-endemic (cases may be travel-related).

  • Diagnosis: Consider TBE in patients with a biphasic febrile illness or any aseptic meningitis/encephalitis during tick season, especially if there is travel history to or from endemic areas (e.g. Central Europe, Baltic region, etc.). In the first phase, TBE can present as a nonspecific febrile illness; after an asymptomatic interval, the second phase may involve meningitis or encephalitis. Laboratory confirmation is typically by serology: detection of TBEV-specific IgM (and IgG) in serum and/or cerebrospinal fluid. PCR is generally not sensitive in late phase, but can detect the virus in blood early in infection.

  • Reporting: TBE is usually a mandatorily reportable disease. Any confirmed or suspected case should be reported to public health authorities, even if infection was likely acquired abroad, to improve surveillance data. This helps assess emerging risk areas and promotes vaccine recommendations.

  • Clinical Management: There is no specific antiviral treatment for TBE. Management is supportive, focusing on managing neurologic symptoms and preventing complications. This may include hospitalization for observation, analgesics and antipyretics for fever and pain, antiemetics for vomiting, and in severe cases, intensive care support for patients with encephalitis (airway protection, management of raised intracranial pressure, seizures, etc.). Administer IV fluids and ensure adequate nutrition. Some countries use TBE immune globulin for post-exposure prophylaxis, but its efficacy is controversial and it’s not widely available. The best protection is preventive – advise healthcare colleagues and patients about the TBE vaccine for those in endemic regions or travelers.

Other Tick-Borne Diseases

Aside from CCHF, Lyme, and TBE, the Balkans region faces occasional cases of other tick-borne illnesses:

  • Mediterranean Spotted Fever (MSF): Caused by Rickettsia conorii and transmitted by dog ticks (Rhipicephalus sanguineus). Presents with high fever, headache, rash, and often a black eschar (tache noire) at the bite site. Diagnosis is by serology (Weil-Felix test is outdated; use specific ELISA/IFA for rickettsial antibodies) or PCR on biopsy of the eschar. Treatment: Doxycycline is the first-line therapy (even for children in these infections), and it typically leads to rapid improvement.

  • Tularemia: Caused by Francisella tularensis (various transmission routes, including tick bites). It can present as ulceroglandular disease (skin ulcer at bite with swollen lymph nodes) or other forms (glandular, oculoglandular, etc.). Diagnosis is via serology or culture/PCR (be aware culture requires high biosafety lab due to infectivity). Treatment: Streptomycin or gentamicin are first-line; doxycycline or ciprofloxacin are alternatives for mild cases. Tularemia is typically notifiable, as outbreaks (often linked to contaminated water or rabbit meat) occur sporadically.

  • Babesiosis: Caused by protozoan parasites (like Babesia divergens or Babesia microti) transmitted by ticks. It can cause malaria-like illness with fever, hemolytic anemia, and jaundice (more severe in asplenic or immunocompromised patients). Diagnosis is by identifying the parasite on Giemsa-stained blood smears or by PCR. Treatment: combination of atovaquone + azithromycin is commonly used for mild to moderate cases; severe cases may require exchange transfusion and clindamycin + quinine.

  • Anaplasmosis/Ehrlichiosis: Bacterial infections (Anaplasma phagocytophilum, Ehrlichia chaffeensis, etc.) causing fever, headache, leukopenia, thrombocytopenia, and elevated liver enzymes. Diagnosis: by PCR of blood, or serology (acute and convalescent titers). Treatment: Doxycycline promptly, as delaying treatment can lead to complications. Most patients recover quickly with therapy.

Surveillance and Reporting: All tick-borne diseases should be reported per national guidelines. Enhanced surveillance is crucial – for instance, rickettsial diseases and tularemia may be under-reported due to non-specific presentation. Cross-border communication is also important: ticks and wildlife do not respect borders, so sharing data (e.g., through the SENTINEL network and BAVBD) about cases and pathogen prevalence helps the entire region. Medical professionals are encouraged to remain alert for these diseases, report cases promptly, and partake in continuous education on vector-borne disease management. By working together, public health and medical communities in the Balkans can better prevent and respond to tick-borne disease threats.