Practice notes from our doctors

Partial immunity to malaria is built up through repeated infections and fades within a few years of living somewhere without malaria. Ghanaians visiting from the UK, Europe or North America are therefore at real risk of severe malaria, and in several of those countries they are the largest group of travellers treated for it.

Prevention has two parts. The first is avoiding bites. The mosquitoes that carry malaria bite mainly between dusk and dawn, so sleep under an insecticide-treated net or in a screened, air-conditioned room, use a repellent containing DEET or picaridin on exposed skin in the evening, and wear long sleeves after sunset.

The second is antimalarial tablets. Several options exist, and the right one depends on the length of your stay, your other medicines, pregnancy and your medical history. Some are started a day or two before exposure and others earlier, and some must be continued for up to four weeks after you leave, so a consultation before or soon after you arrive matters. Please don't rely on herbal preparations or tablets left over from a previous trip.

Any fever during your stay, or in the three months after you leave, should be treated as possible malaria until a test says otherwise. A rapid test takes about 20 minutes. If you become unwell after returning abroad, tell the doctor that you have been in Ghana.

The 'yellow card' is the International Certificate of Vaccination or Prophylaxis. It records your yellow fever vaccination and must be signed and stamped by an approved vaccinating centre. Keep it with your passport: airlines can ask for it at check-in as well as on arrival.

Since 2016 the World Health Organization has recognised a single dose of yellow fever vaccine as giving lifelong protection, and certificates are now valid for life, including older cards that show an expiry date. Most people do not need a booster for travel.

A certificate only becomes valid 10 days after your first vaccination. If your trip is close, book at least two weeks before your flight.

Yellow fever vaccine is a live vaccine and is not suitable for everyone. Babies under nine months, people with weakened immune systems and those with a severe egg allergy need an individual assessment, as do pregnant or breastfeeding women and adults over 60. When the vaccine isn't advisable, a doctor can issue a medical exemption letter, which many countries accept.

Lost your card? A replacement can only be issued from verified vaccination records. Cards obtained without vaccination are fraudulent, leave you unprotected and can lead to refused boarding.

The Widal test looks for antibodies against the bacteria that cause typhoid. Many people in Ghana carry these antibodies from past infections, vaccination or exposure to related bacteria, so the test is often positive in people who do not have typhoid. It can also be negative early in a genuine infection.

As a result, many people take antibiotics for typhoid they don't have. That exposes them to side effects, delays the real diagnosis and adds to antibiotic resistance, which is now a serious problem in typhoid itself.

When typhoid is a genuine possibility, a blood culture remains the most reliable test, alongside a careful history and examination. Results take two to five days. For most short fevers, the first steps are a malaria test and a proper assessment, not a Widal.

If you have been told you had 'typhoid' several times on the basis of Widal results alone, it is worth discussing with a doctor. A fever lasting more than a few days, or fever with abdominal pain, always deserves a full assessment.

Blood pressure varies through the day and often rises in a clinic, the so-called white coat effect. Current guidelines recommend confirming a raised clinic reading with home or 24-hour monitoring before starting treatment, and home readings are the best way to see whether treatment is working.

Use a validated upper-arm machine rather than a wrist device, and check the cuff size: a cuff that is too small reads falsely high. Sit for five minutes with your back supported, feet flat on the floor and your arm resting at heart level. Don't talk, and avoid coffee, exercise and cigarettes for 30 minutes beforehand.

Take two readings a minute apart, morning and evening, for seven days, and write them all down. Bring the list, or the machine itself, to your appointment. We usually set aside the first day and average the rest.

Don't stop or change prescribed medicines because of a few good readings. It is also worth watching hidden salt: for many households in Ghana, stock cubes, salted fish and processed foods contribute more salt than the salt shaker does.

A reading above 180/120 together with chest pain, breathlessness, weakness, confusion or a severe headache needs urgent care. Call 112 or 193.

Sugar in the blood attaches to haemoglobin in red blood cells. Because red cells live for around three months, HbA1c reflects your average blood sugar over that period. You don't need to fast for it, which makes it convenient for screening and monitoring.

As a general guide, a result below 5.7% (39 mmol/mol) is in the normal range, 5.7 to 6.4% (39 to 46 mmol/mol) suggests a raised risk of developing diabetes, and 6.5% (48 mmol/mol) or above is consistent with diabetes, usually confirmed by a second test. Targets for people already living with diabetes are individual and agreed with your doctor.

The caveat is that anything affecting the lifespan of red blood cells affects HbA1c. Anaemia, recent blood loss or transfusion, pregnancy, kidney disease and inherited haemoglobin variants such as sickle cell trait, HbC and sickle cell disease, all common in Ghana, can make the result falsely high or low depending on the laboratory method.

If your HbA1c doesn't fit your symptoms or finger-prick readings, or you know your genotype includes S or C, we may use fasting glucose, a glucose tolerance test or fructosamine instead. Knowing your genotype helps us choose the right test.

Fast for 10 to 12 hours before your appointment. Water is fine, and you should take your usual medicines unless your doctor has advised otherwise. If you take insulin or tablets that can lower your blood sugar, please call us beforehand for specific advice.

Avoid alcohol for 48 hours and strenuous exercise the day before. Both can temporarily change liver enzymes, triglycerides, kidney markers and muscle tests, which can lead to unnecessary repeat testing.

Bring a list of your current medicines and supplements, previous results or reports, and your family history if you know it, particularly heart disease, diabetes, stroke or cancer in parents or siblings at a young age.

Wear comfortable two-piece clothing for the ECG and ultrasound. Women who are menstruating may prefer to move the urine test and cervical screening to another day; let us know and we will arrange it.

Plan for about three and a half hours. Breakfast is served once the fasting samples are taken, and your results consultation is booked before you leave.