Blood cultures from a woman in a surgical intensive care unit grow a yeast after three weeks of broad-spectrum antibiotics, total parenteral nutrition and a femoral central line. The laboratory reports a Candida species that its biochemical panel could not name with confidence, resistant to fluconazole on testing, and the same yeast has been recovered from the bed rails and blood pressure cuff of the patient in the adjacent bay. She remains febrile at 38.9 degrees C on meropenem, with no other focus of infection found. Which organism and which single infection-control action fit best?

Candida auris; contact precautions with single-room isolation

Candida glabrata; airborne precautions

Candida albicans; standard precautions only

Candida tropicalis; cohorting of patients without any change in cleaning

Under the One Health approach, which action best illustrates its core principle?

Joint human, animal and environment surveillance for a shared pathogen

Faster antibiotic supply to district hospitals

A single national vaccine store serving every health programme in the country

Separate reporting formats for veterinary and medical services

In the casualty at night, a man who nursed his brother through a fatal illness two weeks earlier has fever, severe headache, vomiting, brisk myoclonus, absent gag reflex and worsening respiratory distress. The brother had developed encephalitis after drinking raw date-palm sap from a tree where bats roost, and died in another district hospital. His temperature is 39.1 degrees C, pulse 110 per minute and oxygen saturation 92% on room air, and samples are being arranged for the designated high-containment laboratory. Which action protects the treating team best meanwhile?

Isolation with droplet, contact and airborne precautions

Standard precautions alone, since spread requires a bat bite or raw sap

Terminal cleaning only after discharge

Mask for the patient with no change for staff

During the post-monsoon months a tea-estate worker in the Nilgiris has fever for eight days with headache and myalgia. There is a necrotic ulcer with a black crust in the left axilla, tender regional nodes, and crepitations at both bases. Alanine aminotransferase is 142 U/L and the platelet count is 90,000/microL. Which test confirms the likely diagnosis most reliably at this stage?

IgM ELISA for Orientia tsutsugamushi

Peripheral smear examination for malarial parasite

A man returning from West Africa has fever, tender cervical and inguinal lymphadenopathy, and firm, deep-seated umbilicated skin lesions on the face, palms and genitals, all in the same stage of evolution. Mpox is suspected and lesion swabs are sent. Which feature best separates this from varicella?

Monomorphic lesions with lymphadenopathy

Lesions sparing the palms and soles

Successive crops of lesions at different stages of evolution

Emerging and re-emerging infections

16 NEET-PG practice questions on Emerging and re-emerging infections, part of Microbiology. The first 16 are below; the first 5 with answers and explanations (tap Show answer after you have chosen), the rest in Learn with a free account.

Question 1 · Medium
Blood cultures from a woman in a surgical intensive care unit grow a yeast after three weeks of broad-spectrum antibiotics, total parenteral nutrition and a femoral central line. The laboratory reports a Candida species that its biochemical panel could not name with confidence, resistant to fluconazole on testing, and the same yeast has been recovered from the bed rails and blood pressure cuff of the patient in the adjacent bay. She remains febrile at 38.9 degrees C on meropenem, with no other focus of infection found. Which organism and which single infection-control action fit best?
1. ACandida glabrata; airborne precautions
2. BCandida auris; contact precautions with single-room isolation
3. CCandida albicans; standard precautions only
4. DCandida tropicalis; cohorting of patients without any change in cleaning
Show answerHide answer
Answer: B · Candida auris; contact precautions with single-room isolation
Candida auris is commonly misidentified by conventional systems, is often fluconazole-resistant and persists on skin and surfaces, so it spreads between patients in critical care units. Confirmed or suspected cases need single-room isolation with contact precautions, dedicated equipment, chlorine or hydrogen-peroxide-based cleaning and screening of contacts. Key point: Candida auris: misidentified, often fluconazole-resistant, persists on surfaces; isolate with contact precautions.
- A: C. glabrata is fluconazole-resistant but is not transmitted by air.
- C: C. albicans is easily identified and usually fluconazole-susceptible; it does not spread this way.
- D: Cohorting without changed cleaning fails because this yeast survives on surfaces.
Question 2 · Easy
Under the One Health approach, which action best illustrates its core principle?
1. AFaster antibiotic supply to district hospitals
2. BJoint human, animal and environment surveillance for a shared pathogen
3. CA single national vaccine store serving every health programme in the country
4. DSeparate reporting formats for veterinary and medical services
Show answerHide answer
Answer: B · Joint human, animal and environment surveillance for a shared pathogen
One Health recognises that most emerging infections are zoonotic, so human health, animal health and the environment must be watched and acted on together. In practice this means shared surveillance data, joint outbreak investigation teams and coordinated antimicrobial stewardship across human and veterinary sectors. Key point: One Health means joint human, animal and environmental surveillance and response to shared pathogens.
- A: Drug logistics is important but is not what One Health means.
- C: A common vaccine store is a supply-chain measure, not intersectoral surveillance.
- D: Separate formats work against the data-sharing One Health requires.
Question 3 · Medium
In the casualty at night, a man who nursed his brother through a fatal illness two weeks earlier has fever, severe headache, vomiting, brisk myoclonus, absent gag reflex and worsening respiratory distress. The brother had developed encephalitis after drinking raw date-palm sap from a tree where bats roost, and died in another district hospital. His temperature is 39.1 degrees C, pulse 110 per minute and oxygen saturation 92% on room air, and samples are being arranged for the designated high-containment laboratory. Which action protects the treating team best meanwhile?
1. AIsolation with droplet, contact and airborne precautions
2. BStandard precautions alone, since spread requires a bat bite or raw sap
3. CTerminal cleaning only after discharge
4. DMask for the patient with no change for staff
Show answerHide answer
Answer: A · Isolation with droplet, contact and airborne precautions
Nipah virus infection presents as encephalitis with brainstem and respiratory features and spreads person to person through respiratory secretions, which is why family members and health workers are at high risk. Suspected cases are isolated at once with droplet, contact and airborne precautions, and samples go to a designated high-containment laboratory. Key point: Nipah spreads from patient secretions: isolate suspects and use full respiratory and contact precautions.
- B: Human-to-human spread through secretions is well recognised, so standard precautions are not enough.
- C: Cleaning must be continuous during care, not only at discharge.
- D: A mask on the patient alone leaves staff unprotected during aerosol-generating care.
Question 4 · Medium
During the post-monsoon months a tea-estate worker in the Nilgiris has fever for eight days with headache and myalgia. There is a necrotic ulcer with a black crust in the left axilla, tender regional nodes, and crepitations at both bases. Alanine aminotransferase is 142 U/L and the platelet count is 90,000/microL. Which test confirms the likely diagnosis most reliably at this stage?
1. ABlood culture in bile broth
2. BIgM ELISA for Orientia tsutsugamushi
3. CPeripheral smear examination for malarial parasite
4. DWidal test on paired samples
Show answerHide answer
Answer: B · IgM ELISA for Orientia tsutsugamushi
Fever with an eschar, regional lymphadenopathy, thrombocytopenia and mild hepatitis in a plantation worker is scrub typhus. IgM ELISA against Orientia tsutsugamushi is the practical confirmatory test from about the end of the first week, while PCR from the eschar or blood helps earlier. Doxycycline should not wait for the result. Key point: Scrub typhus: eschar with fever; confirm by IgM ELISA in week two, treat with doxycycline at once.
- A: Bile broth culture is used for enteric fever organisms.
- C: A smear detects malaria, which does not cause an eschar.
- D: Widal tests enteric fever and is not relevant to an eschar illness.
Question 5 · Medium
A man returning from West Africa has fever, tender cervical and inguinal lymphadenopathy, and firm, deep-seated umbilicated skin lesions on the face, palms and genitals, all in the same stage of evolution. Mpox is suspected and lesion swabs are sent. Which feature best separates this from varicella?
1. AMonomorphic lesions with lymphadenopathy
2. BLesions sparing the palms and soles
3. CSuccessive crops of lesions at different stages of evolution
4. DItching that precedes the rash
Show answerHide answer
Answer: A · Monomorphic lesions with lymphadenopathy
Mpox lesions are monomorphic, deep-seated and umbilicated, involve palms and soles, and are accompanied by marked lymphadenopathy. Varicella lesions appear in successive crops, so vesicles, pustules and crusts coexist, and lymphadenopathy is not a feature. Confirmation is by lesion-swab PCR. Key point: Mpox: monomorphic umbilicated lesions with lymphadenopathy, palms and soles involved; varicella is polymorphic.
- B: Palm and sole involvement favours mpox rather than excluding it.
- C: Different stages together is the varicella pattern, not mpox.
- D: Itch is common in varicella and is not discriminating.
Question 6 · Hard
A state sets up a One Health unit after two outbreaks of bat-associated encephalitis and a cluster of leptospirosis in flood-hit blocks. The unit has a veterinary officer, an epidemiologist, a microbiologist and a wildlife biologist, and must choose where to spend its first year. Which arrangement would most improve early detection of the next outbreak?
1. AMore ventilators in medical college intensive care units
2. BA new antibiotic policy for district hospitals
3. CAnnual seroprevalence surveys among school children in each block
4. DShared event-based reporting across veterinary, human and wildlife surveillance
Answer and explanation in LearnFree account
Question 7 · Hard
Two nurses who cared for a confirmed Nipah patient before isolation was started report fever on day 9 of their 21-day follow-up. One of them is breathless with a respiratory rate of 28 per minute. Which combination of actions is most appropriate?
1. ASend both home with paracetamol and repeat the testing after a week
2. BStart oseltamivir and manage both as suspected influenza
3. CIsolate both, test by RT-PCR, give supportive care
4. DTest only the breathless nurse and release the other from follow-up
Answer and explanation in LearnFree account
Question 8 · Medium
A newborn in a district hospital nursery has a head circumference well below the third centile, a sloping forehead with redundant scalp skin, intracranial calcifications on ultrasound and bilateral macular scarring. The mother lived in an outbreak district through the first trimester and had a rash illness with joint pain at 9 weeks. Which investigation best establishes the cause in the infant?
1. AInfant blood culture
2. BInfant Zika RT-PCR with maternal serology
3. CNewborn hearing screen by otoacoustic emissions
4. DMaternal rubella IgG alone
Answer and explanation in LearnFree account
Question 9 · Easy
During the monsoon, several children aged 2 to 8 years in a Gujarat village die within two days of a brief fever with vomiting, altered consciousness and seizures. Sandflies are abundant in the cracked mud walls of the houses, cerebrospinal fluid shows no bacteria, and the state laboratory confirms Chandipura virus in two samples of cerebrospinal fluid. No child had received Japanese encephalitis vaccine, the deaths are spread across four hamlets, and the district team finds no common water source or food item. Which control measure is most appropriate for the village?
1. AMass chemoprophylaxis with doxycycline for all village children
2. BCulling of village pigs
3. CChlorination of every drinking water source in the village
4. DIndoor residual spraying against sandflies
Answer and explanation in LearnFree account
Question 10 · Hard
An intensive care unit has had four Candida auris bloodstream infections in six weeks despite contact precautions. The isolates are resistant to fluconazole and to amphotericin B, and echinocandin results are awaited. A fifth patient, ventilated with a tunnelled central line, now has candidaemia with the same yeast. What should be done first for him?
1. AStart an echinocandin and remove the central line
2. BStart amphotericin B deoxycholate as salvage therapy
3. CAwait susceptibility results before any antifungal is begun
4. DStart high-dose fluconazole with therapeutic monitoring
Answer and explanation in LearnFree account
Question 11 · Easy
A farmer from Wayanad who keeps backyard poultry is brought to the taluk hospital with three days of fever, dry cough and breathlessness. About twenty birds in his flock died suddenly in the preceding week and he buried them himself without gloves or a mask. His respiratory rate is 32 per minute and oxygen saturation 90% on room air; a throat swab sent to the state laboratory is positive for influenza A H5N1. He has no other illness and takes no regular medication. Four relatives, two of them teenagers, are still handling the surviving birds without masks or gloves. Which measure matters most for those relatives?
1. ASeasonal influenza vaccine given to every household contact at once
2. BAzithromycin for five days with daily temperature charting
3. CSerial chest radiographs for the next two weeks
4. DPersonal protective equipment with oseltamivir prophylaxis
Answer and explanation in LearnFree account
Question 12 · Medium
A district with Aedes breeding in construction sites reports a sharp rise in laboratory-confirmed Zika infections, most of them mild. The district health officer has to choose one surveillance output to guide the response. Which is most useful?
1. AMonthly totals of all febrile illnesses in the district
2. BAnnual seroprevalence surveys in voluntary blood donors
3. CWeekly counts of adult hospital admissions
4. DRegistry of exposed pregnant women with ultrasound follow-up
Answer and explanation in LearnFree account
Question 13 · Medium
A primigravida at 12 weeks attends the antenatal clinic after returning from a district with an ongoing Zika outbreak. She reports three days of low fever with a fine rash, red eyes and joint pain a week earlier, which settled without treatment. She is afebrile now, and the fetal heart is normal on ultrasound. What is the most appropriate next step?
1. ADengue NS1 antigen alone
2. BReassurance, as rash in pregnancy is harmless
3. CImmediate medical termination of pregnancy under the MTP Amendment Act
4. DZika RT-PCR on blood and urine with later fetal ultrasound follow-up
Answer and explanation in LearnFree account
Question 14 · Medium
As the medical officer of a PHC in a district where date-palm sap is collected and sold at the roadside each winter, you are asked to brief the panchayat after a Nipah death in a neighbouring block. Which advice reduces the community's risk most directly?
1. ASleep under insecticide-treated bed nets every night
2. BBoil all drinking water before use
3. CAvoid raw date-palm sap and fruit bitten by bats
4. DVaccinate household pigs annually
Answer and explanation in LearnFree account
Question 15 · Medium
Statements about scrub typhus in India: 1. An eschar is found in every patient. 2. Doxycycline is effective treatment. 3. Acute respiratory distress and acute kidney injury are recognised complications. 4. A single vaccine protects against all strains. Which combination is correct?
1. A2 and 3 only
2. B1 and 2 only
3. C1, 3 and 4 only
4. D3 and 4 only
Answer and explanation in LearnFree account
Question 16 · Medium
Which statement about avian influenza A(H5N1) in humans is correct?
1. ASustained human-to-human transmission is well established worldwide
2. BMost human cases follow direct contact with infected poultry
3. COseltamivir is ineffective against H5N1 infection
4. DCase fatality is lower than that of seasonal influenza
Answer and explanation in LearnFree account

Emerging and re-emerging infections

Under the One Health approach, which action best illustrates its core principle?

Two nurses who cared for a confirmed Nipah patient before isolation was started report fever on day 9 of their 21-day follow-up. One of them is breathless with a respiratory rate of 28 per minute. Which combination of actions is most appropriate?

A district with Aedes breeding in construction sites reports a sharp rise in laboratory-confirmed Zika infections, most of them mild. The district health officer has to choose one surveillance output to guide the response. Which is most useful?

As the medical officer of a PHC in a district where date-palm sap is collected and sold at the roadside each winter, you are asked to brief the panchayat after a Nipah death in a neighbouring block. Which advice reduces the community's risk most directly?

Statements about scrub typhus in India: 1. An eschar is found in every patient. 2. Doxycycline is effective treatment. 3. Acute respiratory distress and acute kidney injury are recognised complications. 4. A single vaccine protects against all strains. Which combination is correct?

Which statement about avian influenza A(H5N1) in humans is correct?