Education Corner

Tetanus Vaccination Who can take the vaccine? Tetanus is a global health problem. The disease occurs almost exclusively in persons who are non-immunised or inadequately immunised. In developing countries, most of the reported cases occur in infants and young children. Tetanus immunisation is administered by injecting tetanus toxoid, usually in conjunction with diphtheria and pertussis vaccines (DTP). For primary vaccination, children should receive the toxoid at 2, 3, and 4 months of age. Booster doses are also given at 18 months, 6 years and 12 years. For primary immunisation of persons above 7 years of age, tetanus vaccine can be given together with a reduced concentration of diphtheria (Td). Usually, three doses of the formulation of tetanus-diphtheria toxoid are used. The first two doses are given 4 to 8 weeks apart and the third dose 6 to 12 months after the second. A Td booster should be used whenever 10 or more years have elapsed since completion of a primary series or the last booster dose.   Primary or booster doses are recommended for travellers to areas with risk. For those who frequently travel to such areas, a ten-yearly booster dose is recommended.   Are there any adverse reactions after an injection? Mild reactions to DTP vaccination are fairly common such as slight fever, soreness or tenderness at the injection site but these are usually associated with the effect of the pertussis component. In less than 1% of the injections, DTP may cause the following complications: high fever (more than 40.5 degrees C.) or high-pitched cry. In about 1 out of 1750 immunisations, DTP can cause the following complications: febrile seizure in children, shock or even collapse. Brain damage is rarely reported after DTP injection. Are there any contraindications? If the child is sick with something more serious than a mild cold, DTP may be delayed until the child gets better. If the child has ever had a convulsion, other brain disorder, or even mal-development after birth, the DTP is often delayed until it is clear that the condition is not worsening or that seizures are under control. If a child has developed the following complications after an initial DTP vaccination, further immunisation may need to be delayed or avioded: seizures or any serious brain problem within 7 days after injection; allergy (mouth, throat or face swelling, or breathing difficulty); high fever ( more than 40.5 degree C.) within 2 days after injection; shock or collapse within 2 days after injection; persistent, uncontrolled crying that lasts for more than 3 hours at a time within 2 days after injection.

Meningococcal Vaccine (ACWY)   What is Meningococcal Infection?  Meningococcal infection is caused by the meningococcal disease of which early symptoms are not obvious. When bacteria invade the bloodstream (Meningococcaemia) or surround the brain and spinal cord lining (meningococcal meningitis), it can cause serious illness and even cause death. Meningococcal infection is not widespread, and therefore it is not included in children vaccines program. However, when there are outbreaks of diseases across China, it is recommended that if your children or relatives need frequent travel to the Mainland, they can consider this vaccine for protection. Who has the risk of infection? The risk of infection is higher among close contacts of patients with meningococcal infections. Certain patients with defective immune systems are also at higher risk. Other risk factors include antecedent viral infection, overcrowding, chronic illness, and active and passive smoking.In general, the risk of acquiring meningococcal infection while travelling is low. However, in sub-Saharan Africa extending from Mali to Ethiopia, particularly in the savanna during the dry season (December to June), disease occurrence is higher, and there is additional risk for visitors who travel "rough" such as backpackers, and those who need to live or work with local people. 

What is Pneumococcal Infection?  Pneumococcal infection represents a wide range of diseases caused by the bacterium Streptococcus pneumoniae (S. pneumoniae / pneumococcus). More than 90 serotypes have been identified. It can be transmitted by droplet spread and contact with respiratory secretions; direct contact is another way of transmission. S.pneumoniae causes a wide spectrum of diseases, including: meningitis: it is a severe type of pneumococcal infection and usually presents with fever, stiff neck and mental confusion, causing long-term problems, such as hearing loss, or even death; pneumonia: it commonly presents with fever, shortness of breath, chills and productive cough, and may result in death in severe cases; and otitis media: it presents with fever, ear pain with or without ear discharge, and may lead to hearing loss in recurrent cases. Pneumococcal Conjugate Vaccine (PCV) A. Why get vaccinated? Pneumococcal conjugate vaccine (PCV) can effectively protect against severe invasive infections due to the serotypes of S. pneumoniae contained in the vaccine. Children aged below 2 years are at risk to severe invasive pneumococcal infection (i.e. meningitis, bacteraemic pneumonia and septicaemia) and are advised to get vaccinated.  In Hong Kong, PCV13 (vaccine consisting of antigens against thirteen pneumococci serotypes) is included in the Hong Kong Childhood Immunisation Programme.  The Scientific Committee on Vaccine Preventable Diseases recommends individuals aged 2 to 64 years with certain high risk conditions* to receive 23-valent pneumococcal polysaccharideas well as PCV 13.  For more details, please refer to the following link: *High risk conditions include: History of invasive pneumococcal disease Immunocompromised states: Asplenia, HIV /AIDS , primary immunodeficiency Immunodeficiencies related to malignancies and transplantation Immunodeficiencies related to use of immunosuppressive drugs / systemic steroid Chronic disease Chronic cardiac, pulmonary, liver or renal disease Diabetes mellitus or Cerebrospinal fluid leakage With cochlear implants (Essential hypertension per se is not considered as a high risk condition) Different factors such as age and clinical condition may affect the risk of pneumococcal disease. Patients with high-risk conditions should discuss with their attending doctors on the most appropriate vaccination regimen. B. When should my child get vaccinated? A child is advised to receive 3 doses of PCV13 in the first year of life (at 2 months, 4 months and 6 months old), and another booster dose at 12 months old. C. The following individuals should NOT receive PCV serious allergic reaction to previous dose of PCV serious allergic reaction to diphtheria toxoid containing vaccine D. What are the side effects? Most people have no serious reactions after receiving PCV.   Occasionally there may be mild fever (usually occur within 3 days after vaccination) or slight redness or swelling around the injection site, but these will gradually subside in a few days. If fever or discomforts persist, or abnormal breathing is observed, please consult a doctor immediately. E. How many types of PCV are available in HK and what are their protection? There are more than 1 type of PCV available in the market of Hong Kong but no one PCV can cover all serotypes of Streptococcus pneumoniae. Personal and environmental hygiene are important measures in preventing pneumococcal infection.  

What is Hepatitis B? Hepatitis B is a type of viral hepatitis that can cause acute hepatitis and may lead to chronic liver diseases like cirrhosis and liver cancer. The incubation period ranges from six weeks to six months. Approximately 5–10% of adults and 70–90% of infants infected with Hepatitis B fail to clear the virus completely and become chronic carriers, serving as sources of transmission.   Is Hepatitis B prevalent?Hepatitis B infection occurs worldwide, with over two billion people having been infected; about 350 million are chronic carriers. It is endemic in Southeast Asia, and Hong Kong has a moderate infection rate.   How is Hepatitis B transmitted?The virus is present in high amounts in the body fluids of infected persons, mainly blood, amniotic fluid, semen, and vaginal secretions. Transmission routes include: Mother-to-child contact: Around childbirth or infancy, infected mothers can transmit the virus to their babies, with a transmission rate as high as 90%. This is the primary route in highly endemic areas like Hong Kong and China. Blood contact: Through cuts, abrasions, mucous membranes contacting infected blood or secretions, sharing needles for drug use, improper sterilization of tattoo, piercing, or acupuncture instruments, and sharing personal items like razors or nail clippers that may cause skin damage. Sexual contact: Unprotected sexual activity with infected persons.   How to prevent Hepatitis B?Hepatitis B is a bloodborne disease; preventive measures align with other blood transmissible diseases: Careful wound cleaning and dressing. Wearing gloves and disinfecting contaminated objects with household bleach when handling blood or bodily fluids. For blood-contaminated surfaces or objects: Clean with absorbent disposable material, then disinfect with a 1:4 bleach-to-water solution for 10 minutes before rinsing. For blood-stained clothing: Soak in a 1:49 bleach-to-water solution for 30 minutes before washing. For bodily fluid contamination: Clean with absorbent material then disinfect with 1:49 bleach solution for 30 minutes before rinsing. Avoid sharing razors, toothbrushes, nail clippers, syringes, or needles. Avoid tattoos, acupuncture, eyebrow embroidery, mole removal unless disposable or properly sterilized equipment is used. Reduce the number of sexual partners, practice safe sex with condoms, and if a partner is infected, get vaccinated promptly. Vaccination:The most effective prevention is the Hepatitis B vaccine, requiring three doses (first and second doses one month apart, second and third doses five months apart). After full vaccination, 90–95% develop lifelong protective immunity. Blood tests before vaccination determine eligibility—only those never infected receive the vaccine.   Who should get vaccinated? Newborns Family members and sexual partners of infected individuals Injection drug users Frequent recipients of blood or blood products Patients on dialysis Healthcare workers exposed to blood or body fluids Can chronic Hepatitis B be cured ? Chronic carriers should have regular medical checkups, including liver function and related tests, and periodic liver ultrasounds. Antiviral medications like entecavir and tenofovir suppress viral replication to reduce liver damage. Immunosuppressive treatments are carefully managed by doctors.   Source: https://www.info.gov.hk/hepatitis/english/hep_b_set.htm

What is colorectal cancer?According to the 2009 statistics from the Hospital Authority’s Hong Kong Cancer Registry, colorectal cancer ranks second among all cancers in Hong Kong in terms of incidence and mortality. Colorectal cancer primarily develops from intestinal polyps through a process that can be symptomless and takes about 10 years. Early detection and removal of polyps can reduce the chance of progression to cancer. Therefore, it is recommended that people aged 50 or above undergo regular colonoscopy screenings. Those with a family history of colorectal cancer or other high-risk factors should consider earlier screening (from age 40 or 10 years before the relative’s diagnosis) and more frequent examinations for prevention. What is a colonoscopy?Colonoscopy is an endoscopic examination of the lower digestive tract using a soft tube about 1.3 cm in diameter with a camera at the tip. It examines areas including the terminal ileum, cecum, colon, rectum, and anus to detect tumors, polyps, inflammation, or bleeding. If needed, doctors may take tissue samples for biopsy or remove polyps during the procedure. Since most colorectal tumors develop from polyps, early detection and polyp removal help reduce disease incidence. As such, colonoscopy is an effective colorectal cancer prevention method. Who should get a colonoscopy? People aged 50 and older Those with a family history of colorectal cancer Individuals with a history of colorectal polyps People with chronic diarrhea Those with blood in the stool People with changes in bowel habits (such as constipation or diarrhea)   What preparation is needed before a colonoscopy? The bowel must be thoroughly cleaned for clear observation, so patients take prescribed laxatives before the procedure. Patients with diabetes, hypertension, heart disease, kidney disease, those on low-salt diets, taking medications, or pregnant or breastfeeding women should inform healthcare providers and follow guidance carefully. Details of all medications, especially those affecting blood clotting or allergies, should be provided. Avoid high-fiber foods 3 days before the exam. Only consume liquids 1 day before the exam. Drink clear, fiber-free drinks up to 4 hours before the exam. Arrive 30 minutes early. Bring a companion—do not drive yourself home. For same-day gastroscopy, fast from solid and liquid foods for 6 hours beforehand. Healthcare staff will explain the procedure and risks, and patients must sign a consent form.   What is the procedure like? Remove metal objects, jewelry, or dentures. Lie on your side with knees bent. Sedation is given through an IV; the procedure usually takes 30–60 minutes depending on complexity. Afterward, rest in the recovery room until sedation wears off. Due to sedation, it’s safest to have a companion for the trip home. Avoid eating for 1–2 hours post-procedure. Some abdominal bloating or mild discomfort may occur. If bleeding, severe pain, or other serious symptoms occur, seek emergency care immediately.   This content is for educational purposes only. Please consult your doctor for personalized medical advice.

  What is Hepatitis C virus? • Hepatitis C virus (HCV) is a small RNA virus that causes liver damage. Like hepatitis B carriers, some hepatitis C carriers develop chronic hepatitis, liver scarring or liver cancer.• The incubation period is 6-9 weeks (ranges from 2 weeks to 6 months).• A majority of people infected with HCV do not have symptoms or signs. If symptoms and signs occur, they are indistinguishable from those of hepatitis A or hepatitis B virus infections. About 80% of acute infections do not clear the virus and chronic infections ensue.• To test for hepatitis C infection, HCV Ab and HCV RNA are used.• The risk of liver failure and liver-related death from HCV increases for those who are co-infected with human immunodeficiency virus (HIV).Epidemiology• Worldwide, HCV prevalence is directly related to the prevalence of persons who routinely share injection equipment and to the prevalence of contaminated parenteral practices in health care settings.• WHO estimates that 2-3% of world population is chronically infected with HCV.• It has been estimated that less than 0.5% of the general population in Hong Kong carry hepatitis C virus, but the infection rate is higher among injecting drug users.   How is Hepatitis C transmitted?Hepatitis C is spread in a similar way as hepatitis B, mainly through blood contact by:• sharing needles or 'works' when shooting drugs,• needlesticks injuries or sharps exposures on the job,• vertical transmission from an infected mother to her baby during labour.Less commonly, a person can get Hepatitis C infection via sexual contact. The risk increases among men who have sex with men, for those who have sexually transmitted infection, engage in rough sex, or are infected with HIV.   How to prevent Hepatitis C?There is no vaccine available against hepatitis C. The following preventive measures should be taken to prevent hepatitis C:• Do not shoot drugs. If you shoot drugs, stop and get into a treatment programme. If you cannot stop, never share needles, syringes, water, or 'works'.• Do not share personal care items (e.g. razors, toothbrushes) that are potentially contaminated with blood.• HCV infected persons should not donate blood, organs, or tissue.• Health care worker should always follow routine barrier precautions and should handle needles and sharps safely.• Use latex condoms correctly and every time when you have sex.How to cure Hepatitis C:• HCV positive persons should be evaluated by their doctor for liver disease.• Drugs, such as Interferon, Pegylated Interferon and Ribavirin, can be used to treat the infection. Treatment should take into consideration of severity of disease, contraindications, and likelihood of successful response.Source: https://www.info.gov.hk/hepatitis/english/hep_c_set.htm