oscopy may show choroidal tubercles and papilloedema, which is found more commonly than in other forms of meningitis. Refer for specialist investigation and treatment. Viral meningitis Viral causes of meningitis include coxsackie, mumps, and echoviruses. Vira l meningitis produces similar clinical features to bacterial infection, but the illness is often less severe. The initial management is the same as for suspected bacterial meningitis . Refer for admission and investigation. Fungal meningitis Fungal meningitis is usually part of disseminated infection in immuno- su ppressed patients, (eg those with AIDS ( b p.242), lymphoma, or on steroid therapy). Crypto coccus neoformans is the commonest organism. Symptoms usually develop slowly, as with TB me ningitis. There may be papilloedema and focal neurological signs. Admit for specialist inve stiga- tion and treatment. 226 CHAPTER 5 Infectious diseases Gastroenteritis/food poisoning ND : 1 Diarrhea is the usual presenting symptom of gastroent eritis, but it may also occur in many other conditions as diverse as otitis media, appendic itis and ulcerative colitis. Antibiotics often cause diarrhea. Constipation may present as diarrhea if there is over \202 ow around an obstructing stool. A rectal tumor may present similarly. A baby \200\231s parents may seek advice about diarrhea when in fact the stools are normal. Breast-fed babies almost always have loose stools, which may be yellow or green and very f requent, often after every feed. However, gastroenteritis is very rare in fully breast-fed babies. In children aged > 6 months, normal stool frequency ranges from 1 stool on alternat e days to 3 stools daily. Diarrhea and vomiting may be caused by many types of bacteria and viruses, and also by some toxins and poisons. Many episodes of gastroenteritis result from contaminated food, usuall y meat, milk or egg products, which have been cooked inadequately or left in warm condition s. The speci \201 c cause is often not identi \201 ed. Some infections are spread by feca l contamination of water (eg cryptosporidiosis from sheep feces). Rotavirus infection (comm on in children) may be transmitted by the respiratory route. Severe illness with bloody dia rrhea, haemolysis and renal failure may result from infection with verocytotoxin producing E. coli (VTEC O157). Stool microscopy and culture are unnecessary in most cases of gastro- enteritis, but obtain them if the patient has been abroad, is severely ill, has prolonged symptoms, comes from a n institution or works as a food-handler. Food poisoning is a noti \201 able disease ( b p .221). Immediate noti \201 cation by telephone is mandatory if an outbreak is suspected. T he food eaten, symptoms and incubation period may suggest the organism or toxin involved (s ee Table 5.1). Carbon monoxide poisoning ( b p.208) may cause malaise and vomiting in sever al members of a family and be misdiagnosed as food poisoning. History Record the duration of symptoms and the frequency and description of stools and vom it. Document other symptoms (eg abdominal pain, fever), food and \202 uid ingested and dr ugs taken. Enquire about affected contacts, foreign travel and occupation (especially relev ant if a food-handler). Examination Look for abdominal tenderness, fever and other signs of infection. Record the p atient \200\231s weight and compare this with any previous records. Assess the degree of de hydration \200\224 this is traditionally classi \201 ed as mild (<5 % ), moderate (5 \200 \22310 % ), or severe ( > 10 % ), as outlined opposite. 227 GASTROENTERITIS/FOOD POISONINGND: 1 Clinical evidence of mild dehydration (<5%) \200 Thirst. \200 d urinary output (in a ba by <4 wet nappies in 24hr). \200 Dry mouth. Clinical evidence of moderate dehydration (5 \200\22310%) \200 Sunken fontanelle in infants. \200 Sunken eyes. \200 Tachypnoea due to metabolic acidosis. \200 Tachycardia. Clinical evidence of severe dehydration (>10%) \200 d skin turgor on pinching the skin. \200 Drowsiness/irritability. Table 5.1 Food poisoning characteristics Symptoms * Cause Incubation Food Staph. aureus 1 \200\2236 hours Meat, milk D, V, P, shock Bacillus cereus 1 \200\22316 hours Rice D, V, P Salmonella 6 \200\22348 hours Meat, eggs D, V, P Escherichia coli 1 \200\2232 days Any food D, V, P E. coli VTEC 0157 1 \200\2232 days Meat, milk D, V, P Campylobacter 1 \200\2233 days Meat, milk Fever, P, D Shigella 1 \200\2233 days Any food Bloody D, V, fever Vibrio parahaem 2 \200\2233 days Seafood Watery D Cholera 12hr \200\2236 days Water, seafood D (watery), shock Rotavirus 1 \200\2237 days D, V, fever, cough Botulism 12 \200\22396 hours Preserved food V, paralysis <1 hour Fish Flushing, headache, D, V, P ( b p.229) Histamine \201 sh poisoning (scombrotoxin) D, V, P, paraesthesiae, muscle weakness ( b p.229) Fish from tropical coral reef Ciguatera \201 sh poisoning 1 \200\2236 hours (rarely 30 hours) Paralytic shell \201 sh poisoning 30 min \200\223 10 hours Shell \201 sh Dizziness, paraesthesiae, weakness, respiratory failure ( b p.229) Chemicals <2 hours Food, water Various Mushrooms <24 hours Mushrooms D, V, P, hallucinations ( b p.212) D = diarrhea, V = vomiting, P = abdominal pain. 228 CHAPTER 5 Infectious diseases Gastroenteritis/food poisoning ND : 2 Treatment Most cases are self-limiting, but careful a ttention is needed to ensure adequate \202 uid replacement and also to prevent cross-infe ction ( b p.32). Hospital treatment is needed if the patient looks seriously ill, dehydrati on is > 5 % , there is a high fever or the family are unlikely to cope with the patient at home. Babies aged <3 months may be dif \201 cult to assess and can deteriorate rapidly \200\224 refer for admission. Severely dehydrated ( > 10 % ) children need immediate IV \202 uids, initially 0.9 % saline (10 \200\22320mL/kg over 5min, repeated as necessary). Oral rehydration therapy (ORT) is effective in most patients with gastro- enteritis (<5 % d ehydration). Standard ORT products (eg Dioralyte ) contain glucose, sodium, potassium, c hloride and citrate (details in BNF ). Glucose is important to enhance absorption of sodium and water. Usual dose of ORT: infant 1 \200\2231 times usual feed volume. child 200mL after each loose stool. adults 20 0 \200\223400mL after each loose stool. Extra ORT can be given if the patient is still thirsty. Frequent small sips are usually tol erated better than a large drink. Check that the patient (or parent/carer) can understand t he instructions supplied with the ORT sachets or effervescent tablets and can measure the n ecessary amounts of clean water. Recommence normal feeds and diet after 24hr (or earlier if diarrhea has settled or the patient is hungry). Give further ORT if the diarrhea continues . A child with acute diarrhea requires daily review (usually by the GP), but should be seen earlier if he becomes more ill (especially if drowsy or pyrexial), or if vomiting and/or d iarrhea worsens. Home-made salt and sugar mixtures may be dangerously inaccurate for ORT, b ut if nothing else is available, one could use salt 2.5mL (half a 5mL spoonful) and sugar 2 0mL (4 \227 5mL spoonfuls) in 1 pint (500mL) of cooled boiled water. Drugs other than ORT are rarely needed in gastroenteritis. In adults an anti-emetic (prochl orperazine 12.5mg IM or 3mg buccal) may be helpful, but in children prochlorperazine often causes troublesome side effects. However, oral ondansetron (0.1 \200\2230.15mg/kg, max 8mg) reduces vomiting and the need for IV \202 uids and admission. Prolonged vomiting require s investigation and hospital admission. Anti-diarrhoeal drugs (eg kaolin, codeine phosphate, loperamide) are contraindicated in chi ldren and rarely needed in adults: they may aggravate nausea and vomiting and occasionally cause ileus. Antibiotics are only needed in special circumstances. Most episodes of gastroenteritis are brief and many are caused by viruses and not helped by antibiotics. Patients with amoebiasi s, giardiasis, Campylobacter or Shigella infections may need antibiotics: refer to an Infec tious Diseases unit for treatment and follow-up. Antibiotics are occasionally useful in tra veler \200\231s diarrhea before a long journey or an important meeting: trimethoprim (200mg bd PO for 5 days) or cipro \202 oxacin (500mg bd PO for 2 days: see the BNF or data sheet about side effects and warnings). 229 FISH POISONING Fish poisoning Histamine \201 sh poisoning Also known as scombroid \201 sh poisoning or scombrotoxin poisoning, this is caused by ingesting toxins in \201 sh such as tuna, mack erel, and other dark- meat \201 sh, which have been stored improperly. If the \201 sh i s not cooled rapidly after it is caught, an enzyme in bacteria converts histidine into his- tamine and other toxins, which are heat-stable and so are unaffected by cooking. The patie nt may notice that the \201 sh tastes metallic, bitter, or peppery and the \202 esh loo ks honeycombed. Symptoms start within a few minutes to 2 hours, with \202 ushing of the f ace and upper body, headache, nausea, vomiting, abdominal pain, diarrhea, dizziness and pal pitations. Urticaria and bronchospasm are less common. The symptoms usually settle within 6 hours without treatment, but resolve more quickly with antihistamines (eg chlorphenamine 1 0mg IV in adults, 250 micrograms/kg in children). In severe cases cimetidine and, rarely, a drenaline might be needed, with oxygen, IV \202 uids and bronchodilators. The patient should be told that histamine \201 sh poisoning is caused by improper \201 sh handling and storage. It is not an allergic reaction and so the patient would not have t o avoid eating \201 sh in future. Ciguatera \201 sh poisoning This is caused by a neurotoxin called ciguatoxin which is pro duced by a dino \202 agellate (a unicellular plankton) associated with coral reefs. Fish i mported from the tropics may cause ciguatera poisoning in the UK and elsewhere. Symptoms us ually start 1 \200\2236 hours after ingestion with nausea, vomiting, watery diarrhea and ab dominal pain, followed by neurological symptoms, including paraesthesiae of the lips, tongu e and feet, ataxia and muscle weakness. A classic feature is paradoxical temperature revers al (cold objects feel hot and hot objects feel cold). Alcohol makes these symptoms worse. B radycardia and hypotension may occur. Treatment is symptomatic and supportive. Gastro-intes tinal symptoms usually settle within 1 day, but paraesthesiae may persist for weeks or mont hs. Paralytic shell \201 sh poisoning This can be caused by eating molluscs such as mussels, c lams, cockles and scallops which concentrate a neurotoxin called saxitoxin produced by dino \202 agellate plankton. This plankton proliferates when sea temperatures rise in summer a nd may make the sea look red ( \200\230red tide \200\231). Symptoms start 30 minutes to 10 hours after ingestion, with dizziness, ataxia, paraes- thesiae and muscle weakness, which m ay progress to respiratory failure. Treatment is supportive, with assisted ventilation if n ecessary. Complete recovery is usual within 24 hours. 230 CHAPTER 5 Infectious diseases Infestations Worms The most common helminthic infection seen in the UK is the thread- worm Enterobius vermicularis . This causes anal itching, especially at night. Sometimes intact w orms (length 5 \200\22313mm, diameter 0.1 \200\2230.5mm) are seen in the feces. Unwashed \201 ngers transmit ova from the perianal skin to the mouth. Personal hygiene is important in treatment and in prevention of reinfection (hand-washing and nail-scrubbing before each meal and after every visit to the toilet). A bath immediately after getting up removes ova laid overnight. All members of the family require treatment with mebendazole or piperazine (see BNF ). Other helminthic infections include roundworms, hookworms and tapeworms. Obtain advice from departments of Infectious Diseases or Tropical Medicine (see b p.246). Lice Humans may be infected by the body louse ( Pediculosis humanis corporis ), head louse ( Pediculosis humanis capitis ), or the \200\230crab \200\231/pubic louse ( Phthirus pubis ). Head lice are common in school children. Infection is not related to lack of hygiene or the length of hair. Adult lice are 3 \200\2234mm long, vary in color from white to gray-bl ack and attach themselves \201 rmly to the scalp at the base of hairs. The egg cases ( \200\230nits \200\231) are white and 1 \200\2232mm in diameter, glued \201 rmly to the ba se of hairs and moving outwards as the hair grows. Head lice cause intense itching, which m ay suggest the diagnosis. Secondary infection may result in impetigo. Head lice are usually treated with malathion, phenothrin or simeticone, repeated after 7 days (see BNF ). Drug-r esistant lice occur in some areas. Wet combing to remove head lice takes time and is possib ly less effective than drug treatment. Infection by body lice is related to poor hygiene and infrequent washing of clothes. Body l ice are found in the seams of clothing, and sometimes in body hair. Treatment is with malat hion. Clothes can be disinfected by boiling or by machine laundering and ironing. Body lice may transmit ricketsial diseases (louse-borne typhus) and other infections. Crab lice are usually transmitted sexually. They cause itching in pubic hair areas. Occasio nally, children become infested on eyelashes or eyebrows. Treat with permethrin or malathio n (see BNF ). Sexual partners or other family members may also need treatment. There may be other co-existing sexually transmitted diseases. Fleas There are many different types of \202 ea. They cause itchy bites with linear eryth ematous papules. Treat with calamine lotion and an oral antihista- mine (eg chlorphenamine) if itching is severe. A long-acting insecticide is needed in the house, especially in crac ks in the \202 oor and under furniture. All household cats and dogs must be treated for \202 eas. Fleas can transmit many infections, including plague, typhus and Q fever. 231 INFESTATIONS Scabies Scabies is caused by infestation with a mite, Sarcoptes scabiei , which is about 0. 2 \200\2230.4mm long and burrows into the skin. It is most often found in the \201 nger w ebs and on the \202 exor aspect of the wrists. After 4 \200\2236 weeks, intense itching o ccurs, especially at night or after a hot shower. Burrows (3 \200\22315mm long) may be appa rent, especially on palpation of affected skin. Genital lesions are reddish and nodular. Se condary bacterial infection may occur. Scabies can be con \201 rmed by microscopy of scrap ings from suspected lesions. Treat with permethrin or malathion (see BNF ). Treat all membe rs of the household at once. Calamine lotion and an oral antihistamine may help to relieve itching. Ticks Ticks may be acquired from domestic animals or while walking through undergrowth or e xploring caves. Ticks may be removed with tweezers or curved forceps. They can carry severa l diseases, including Lyme disease (see below), tick-borne encephalitis, typhus, and Rocky Mountain spotted fever. Tick paralysis occurs in North America and Australia, with progress ive paralysis which is often misdiagnosed as poliomyelitis. However, the risk of infection from tick bites is low in most areas, and so routine prophylaxis with antibiotics is not re commended. Lyme disease (Lyme borreliosis) is caused by a tick-borne spirochaete, Borrelia burgdorferi , and occurs in the UK, most of Europe, the USA, and parts of Asia and Australia. Most cas es occur in the summer and early autumn, and are transmitted by ticks from deer or sheep. T he initial tick bite may go unnoticed. Clinical illness develops after about 7 \200\22314 d ays (range 2 \200\22330 days) with an expanding red area around the site of the bite (eryth ema migrans). The second clinical stage of the disease occurs some weeks or months later, w ith fever, muscle and joint pains, and sometimes facial palsy or other cranial nerve or per ipheral nerve palsies. Meningitis, encephalitis and arthritis may develop. Myocarditis and heart block occur occasionally. Refer to an Infectious Diseases specialist for con \201 rm ation and treatment if Lyme disease is suspected. 232 CHAPTER 5 Infectious diseases Tuberculosis ND The Mycobacterium genus is characterized by acid-fast staining (ie it is no t decolourized by acid after staining with hot carbol fuchsin). Infection with Mycobacterium tuberculosis is common throughout the world. There is growing concern about the re-emergence of TB in the UK and other countries. Many cases of TB occur in the lower socio-economic groups, ethnic minorities and the immunocompromised. The incide nce of TB i with age. Presentation TB can involve almost any organ of the body. Primary infection is usually pulmonary and often asymptomatic. Post-primary infection may present with malaise, weight loss and night sweats, with localiz ed symptoms depending on the organs involved. Pulmonary TB may result in cough, haemoptysis, pneumonia and pleural effusion ( b p.103). M iliary TB, with blood-borne infection of many organs, develops over 1 \200\2232 weeks with fever, weight loss, malaise and breathlessness: CXR may show multiple small opacities throu ghout the lung \201 elds, and choroidal tubercles may be visible in the optic fundi. TB meningitis causes headaches and vomiting, sometimes with neck stiffness, cranial nerve p alsies and papilloedema (see b p.224). Tuberculous osteomyelitis usually affects the spine, with collapse of adjacent vertebrae and a paravertebral abscess. Patients may present with swollen lymph nodes from tuberculous lymphadenitis or with sinuse s or cold abscesses from bone or soft tissue infection: microscopy of the discharge will sh ow acid-fast bacilli. Treatment Refer patients with suspected TB to an appropriate specialist for assessment and treatment. Isolation is required for patients with untreated pulmonary TB. Notify the local Health Protection department ( b p.221). 233 ANTHRAXND Anthrax ND Anthrax is caused by the bacterium Bacillus anthracis which affects cows and oth er herbivorous animals, especially in warm climates. The bacte- rium forms spores, which ma y remain infective for years. Most human cases of anthrax are cutaneous anthrax caused by d irect skin contact with infected tissues and occur in people working with animal products s uch as imported hides. Less common, but more serious, are inhalation anthrax caused by inha lation of anthrax spores, and intestinal anthrax which is a rare form of food poisoning cau sed by under-cooked infected meat. Anthrax spores released deliberately in terrorist attack s could cause cutaneous anthrax or inhalation anthrax, which is often fatal. Cutaneous anthrax starts 2 \200\2237 days after infection, with a red papule which develops into an ulcer with a black leathery eschar, surrounded by non-pitting oedema. The lesion i s painless but may itch. Small satellite lesions may surround the original lesion. Malaise and fever may occur, with septicaemia in 10 \200\22320 % of cases. Penicillin d risk of com plications from cutaneous anthrax. Clinical diagnosis is con \201 rmed by microscopy and c ulture of the pustule. Inhalation anthrax starts within 48 hours of exposure (rarely up to 6 weeks) with a \202 u-like illness, followed by breathlessness, cyanosis, stridor and sweating, often with subc utaneous oedema of the chest and neck. CXR and CT show mediastinal widening from lymphadeno pathy and pleural effusions. Shock, septicaemia and meningitis are common and usually fatal , despite antibiotics and intensive treatment. Airborne transmission of anthrax from one person to another does not occur, but cutaneous a nthrax could result from direct contact with anthrax lesions. Obtain expert advice immediat ely if anthrax is suspected. It is a noti \201 able disease ( b p.221). Post-exposure anti biotics can prevent anthrax if started early enough. Press enquiries must be anticipated af ter any case of anthrax, especially if anthrax has been released deliberately. Further info rmation is available from: www.hpa.org.uk/infections . Anthrax in drug users After a serious anthrax outbreak in heroin users in Scotland in 2010, Health Protection Scotland ( www.hps.scot.nhs.uk ) advised doctors to suspect anthrax in a drug user presenting with any of the following: \200 Severe soft tissue infection and/or signs of severe sepsis/meningitis. \200 Clinical features of inhalational anthrax. \200 Respiratory symptoms + features of meningitis or intracranial bleeding. \200 GI symptom s (eg pain, bleeding, nausea, vomiting, diarrhea, ascites). Approach Get expert help early to advise on management (microbiology, hospital infection control team, Public Health, ICU, surgeons). Start IV antibiotics according to advice (eg combination of cipro \202 oxacin, clindamycin + penicillin, or if there is soft tissue infection: cipro \202 oxacin, clinda mycin, penicillin, \202 ucloxacillin + metronidazole). Experts will advise on whether to use anthrax immune globulin. 234 CHAPTER 5 Infectious diseases Streptococcal infections Streptococcus pyogenes and other streptococci may reside in the ph arynx without symptoms, but can cause sore throats ( b p.554), soft tissue infections ( b p p.413 and 528), scarlet fever, and occasionally endocar- ditis and septicaemia. Later, non- suppurative sequelae of streptococcal infections include erythema nodosum, rheumatic fever ( b p.496) and glomerulonephritis. Streptococci and Staphylococci may cause necrotizing fas ciitis, impetigo, and toxic shock. Scarlet fever ND Some streptococcal infections are assoc iated with scarlet fever. A diffuse blanching scarlet rash often involves the neck, chest, axillae and groin. Occlusion of sweat glands makes the skin feel rough, like sandpaper. Dur ing the \201 rst 1 \200\2232 days of illness there is a \200\230white strawberry tongue \200\231, with red papillae protruding through white furry material. After a few days the w hite fur separates, leaving a shiny \200\230raspberry tongue \200\231. 10 \200\22314 days after onset of the rash, skin may peel from palms and soles. Treat with penicillin or eryth romycin for 14 days. Complete recovery is usual. Infective endocarditis Endocarditis may develop on previously normal heart valves, as well as on diseased or prosthetic valves. The commonest organism is Strep. viridans , but many o thers have been implicated. Many acute cases present with heart failure and involve Staphyl ococcus aureus . Injecting drug users are liable to staphyloco- ccal infection of the tricu spid valve, with fever and pneumonia from septic PE. Clinical features Fever and changing m urmurs suggest endocarditis. Emboli may cause strokes. Ask about weight loss, malaise, nigh t sweats. Look for clubbing, splinter hemorrhages, splenomegaly, anemia, microscopic haemat uria. Treatment investigation (blood cultures, echocardiography) and treatment. On suspicion of endocarditis, admit immediately for Cellulitis and erysipelas Treat these bacterial skin infections as described in b p.528. Necrotizing fasciitis This is a rare and severe bacterial infection of soft tissues. It can occur with or without obvious trauma and may follow illicit IM heroin injection ( \200\230 muscle popping \200\231). Strep . pyogenes is often involved, sometimes with Staph. aureus or other bacteria. Often there are both aerobic and anaerobic organisms. Infection involves fascia and subcutaneous tissues, with gas formation and development of gangrene. Infection may spread to adjacent muscles, causing myonecrosis or pyogenic myositis. Similar infectio ns may involve the abdomen and groin (Fournier \200\231s gangrene). Initial symptoms and si gns may be vague, with very severe pain, but little to \201 nd on examination: the affect ed area may be tender, sometimes with slight erythema and swelling. The patient is usually pyrexial. Infection can spread rapidly and cause marked soft tissue swelling with discolour ation, bruising, haemorrhagic blisters, or overlying skin necrosis. Toxic shock may develop and the mortality rate is high. X-rays may show gas in the soft tissues but may be normal. Treatment involves resuscitation with IV \202 uids and antibiotics (penicillin and clind amycin), urgent surgery to debride the affected area and excise necrotic tissues, and inten sive care. 235 STAPHYLOCOCCAL INFECTIONS Staphylococcal infections Staphylococcus aureus is involved in many infections of wounds, s oft tissues ( b p.413), joints and bones ( b p.494 and 705). Staphylococci may also cause i mpetigo, scalded skin syndrome, food poisoning, toxic shock syndrome, endocarditis, pneumon ia, septicaemia and meningitis. Impetigo A highly infectious super \201 cial skin infection caused by staphylococci or str eptococci. It may involve normal skin or complicate a pre-existing condition, such as eczem a or scabies. Lesions often start around the mouth and nose, spreading rapidly on the face and to other parts of the body. Irregular golden-yellow crusted lesions occur, particularly in strep- tococcal infections. Staphylococci may cause bullous impetigo, with bullae conta ining pus which rupture and dry to form crusts. Treat with topical fusidic acid or mupiroci n (usually for 7 days, max. 10 days) and give oral \202 ucloxacillin or erythromycin if l esions are widespread or there is cellulitis or pyrexia. Scalded skin syndrome Staph . aureus may produce an exotoxin causing separation of the oute r layers of the epidermis, large sections of which slide off with minimal pressure, leaving large raw areas resembling a severe scald. Drug allergies can cause similar lesions. Most cases of scalded skin syndrome (toxic epidermal necrolysis, Lyell \200\231s syndrome) occur in children. Admit for nursing and medical care. Toxic shock syndrome This is caused by exotoxins from Staph. aureus or (less commonly) Stre p . pyogenes . Some cases during menstruation are related to tampons, other cases occur aft er surgical operations, burns, other trauma, or local infections. There is high fever, a ge neralized erythematous rash, confusion, diarrhea, muscle pains, hypotension, and renal fail ure. Subsequently, scales of skin separate from hands and feet. Death may occur from multip le organ failure. Treat for septic shock with IV \202 uids and anti-staphylococcal antibi otics. Remove tampons and send for culture. Refer to ICU. Involve a surgeon if an associate d abscess requires drainage. Staphylococcal septicaemia Occurs particularly in debilitated or immune-compromised patient s and in injecting drug users. There may be endocarditis with metastatic infection of lungs , bone or soft tissues and gangrene due to emboli or arterial thrombosis. Signs of meningit is and DIC may suggest meningo- coccal septicaemia ( b p.224) and the rash may be similar. Meticillin resistant Staphylococcus aureus (MRSA) MRSA causes particular concern because of antibiotic resistance and is carried by many asymptomatic people (patients and staff). Tra nsmission is minimized by hand washing ( b p.32) and other infection control measures. An i nformation lea \202 et about MRSA for patients is available at www.hpa.org.uk/infections/t opics_az/staphylo/mrsa_lea \202 et.htm