2nd half of my ppt on emerging and re-emerging diseases. i uploaded the first half already. pls refer to that too. this ppt has info on AIDS/HIV, ZIKA, EBOLA-MARBURG, MELIODIOSIS, CHOLERA and ANTIMICROBIAL RESISTANCE

1. Emerging & Re-emerging Infections-II
Dr. Mamta T.G.
Asst Prof Comm Med
MMC

2. AIDS
1. AIDS was first described in 1980s in a report from CDC.
2. Two years later the causative virus was identified and afterwards named the HIV.
3. HIV has spread throughout the world, killing half of the 60 million people infected
thus far.
4. Currently, there are about 2 million new HIV infections each year and an equal
number of deaths due to AIDS.
5. Recent trend in HIV diversity is the increased proportion of circulating recombinant
virus forms.
6. Though modes of transmission are the same as other HIVs.
7. the extraordinary sequence diversity of prevalent presents a major challenge for host
immune responses, treatment, and vaccine approaches.

3. DENGUE
1. First isolation of dengue virus (DENV) in 1943.
2. Number of cases are increasing every decade.
3. Increased urbanization along with substandard housing, unreliable water supply,
and poor sanitation provide an environment for Aedes aegypti proliferation in close
proximity to human hosts.
4. According to the United Nations Population Division, between 2000 and 2030, Africa
and Asia together are expected to account for four-fifths of all urban growth in the
world.

4. Ebola and Marburg viruses
(Filoviridae family)
of origin

5. EBOLA

6. Transmission

9. MELIOIDOSIS
1. An infectious disease endemic in South-East Asia and the 'Top End' of Australia.
2. Caused by the bacterium Burkholderia pseudomallei
3. Common mode of transmission -direct inoculation of contaminated soil and
surface water through skin abrasions.
4. Others- Human-to-human transmission, transmission through inhalation of
polluted water and contact with contaminated ground water have been reported
5. The prevalence of melioidosis is highest amongst immunocompromised
individuals and those with significant comorbidities.
6. Diabetes mellitus is the most important host risk factor for the disease.
7. Continual occupational exposure to soils and ground water contributes to an
increased risk of contracting melioidosis, placing rice farmers and labourers at
greater risk.

11. Diagnosis and treatment
1. A diagnosis of melioidosis can be a very difficult outside of endemic regions.
2. The definitive diagnosis is made when B. pseudomallei is recovered from any
site - it is never normal flora.
3. Complete screening of patients is recommended (blood, sputum, urine, pus
culture and throat swab).
4. CT scans or ultrasound of the abdomen to check for subclinical abscesses,
particularly of the prostate, which is an area with a high incidence of abscesses
in northern Australia.
5. Clinical management has two main phases:
a. the intravenous intensive phase for treatment of acute disease-intravenous ceftazidime
(2 g, 6 hourly) or meropenem (1 g, 8 hourly) plus high-dose cotrimoxazole
b. the eradication phase- Three months of oral antibiotic therapy -high-dose cotrimoxazole

12. Swine flu
1. Swine influenza is a respiratory infection common to pigs worldwide caused by
type A influenza viruses, subtypes H1N1, H1N2, H2N1, H3N1, H3N2, and H2N3.
2. Can cause moderate to severe illness in humans and affect persons of all age
groups.
3. People in close contact with swine are at especially high risk.
4. The World Health Organization declared an H1N1 pandemic on June 11, 2009,
after more than 70 countries reported 30,000 cases of H1N1 infection.
5. In 2015, incidence of swine influenza increased substantially to reach
a 5-year high.
6. In India in 2015, 10,000 cases of swine influenza were reported with 774
deaths.

14. Bird flu
• Influenza A viruses cause yearly epidemics and occasional pandemics.
• Infect humans and may cause severe respiratory disease and fatalities.
• Transmitted through many strains-
H5N1
H7N9
H9N2
H10N8

15. transmitted

17. ZIKA
1. Zika virus was originally identified in the Zika Forest of
Uganda in 1947.
2. The virus family Flaviviridae, genus Flavivirus,
and transmitted by Aedes mosquitoes.
3. The early clinical picture of natural human Zika virus infection was of a short
duration, self-limiting, mild febrile illness that was accompanied by a maculopapular
rash.
4. Currently, manifests as mild infection with fever and rash as the main symptoms, and
sore throat, muscle and joint pain, and headache as other reported symptoms.
5. Severe cases- Guillain-Barré syndrome, meningoencephalitis, microcephaly.
6. Temporal relation between Zika virus infection in the mother during the first
trimester and microcephaly.

23. CHANDIPURA VIRUS
1. Chandipura Virus (CHPV), a member of Rhabdoviridae, is responsible for an
explosive outbreak in rural areas of India.
2. It affects mostly children and is characterized by influenza-like illness and
neurologic dysfunctions.
3. It is transmitted by vectors such as mosquitoes, ticks and sand flies.

24. Clinical signs/symptoms
1. acute onset fever, altered
sensorium, seizures,
diarrhea, and vomiting
2. acute encephalopathy
syndrome
3. aseptic meningitis
4. acute neurological illness of
young children with high
case-fatality

25. Diagnosis, treatment and Prevention
1. An effective real-time one step reverse-transcriptase PCR assay method is
adopted for diagnosis of this virus.
2. There is no specific treatment available to date, symptomatic treatment
involves use of mannitol to reduce brain edema.
3. A Vero cell based vaccine candidate against CHPV was evaluated efficiently as
a preventive agent against it. Prevention is the best method to suppress CHPV
infection.
4. Containment of disease transmitting vectors, maintaining good nutrition,
health, hygiene and awareness in rural areas will help in curbing the menace
of CHPV.

26. CHOLERA
1. Cholera, an acute waterborne diarrhoeal disease, continues to be a significant global
health threat.
2. The currently ongoing seventh pandemic of cholera, which started in 1961, has been
reported in over 50 countries and has affected over 7 million individuals.
3. It is affecting all ages and is primarily due to unhygienic living conditions, poverty and
lack of clean drinking water.
4. World Health Organization (WHO) estimates that 3–5 million cholera cases occur every
year, leading to 100,000–120,000 deaths due to cholera every year with an average case
fatality rate of 2.25 % (range 1–10 %)
5. Its actual mortality and morbidity is underestimated due to gross under-reporting,
growing risks due to climate change, increased bacterial virulence (new variants of O1 El
Tor) and emergence of antibiotic resistance, etc.
6. In May 2011, the World Health Assembly (WHA) recognised the re-emergence of cholera
as a significant global public health problem

28. Problem statement
1. 130 % increase in the number of cases of cholera from 2000 to 2010
2. Endemic in approximately 50 countries
3. The situation is critical in Asia where the disease is both endemic and
epidemic
4. The coastal regions of South Asia, for example Bangladesh and Kolkata in
the state of West Bengal in India, have a long history of cholera outbreaks
and are collectively considered the native homeland of the cholera disease
since the early nineteenth century

29. Cholera in India
1. Cholera seasonality in the Bengal delta region is unique -it shows two cholera
outbreaks in a given annual cycle.
2. Spring outbreaks are the results of intrusion of coastal water in the Bay of
Bengal aided through low river discharge, while the autumn cholera
outbreaks are the result of flooding caused by high river discharge.
3. Importantly, cholera incidence in this region has been historically linked to
environmental and climate variables such as precipitation, floods, river level,
sea surface temperature, coastal salinity, dissolved organic material and
faecal contamination.
4. Ponds known as pukurs in common Bengali parlance are a source of V.
cholerae for cholera outbreaks, as many country folk use the water not only
for washing purposes but also for drinking purposes.

30. Cholera in India
1. India- 66.6 % rural population, only 28 % - piped drinking water, 26 % access to
good sanitation.
2. Over the last decade, a large number of cholera outbreaks have occurred in
India, with the highest frequency in West Bengal and Odisha.
3. The other states which have reported cholera outbreaks include Tamil Nadu,
Karnataka, Gujarat, Andhra Pradesh, Maharashtra, Punjab, Haryana and Delhi.
4. Telangana-Thirty-four V. cholerae isolates collected from a cholera outbreak in
Hyderabad, Andhra Pradesh in 2010, were found to belong to serogroup O1
biotype El Tor serotype Ogawa.
5. The results of this study suggest that altered El Tor biotype V. cholerae with
the classical cholera toxin gene are involved in cholera outbreaks in India.

36. Antibiotic resistance
1. ‘Resistance to an antibiotic’ -when a microorganism is able to grow or survive
in the presence of a concentration of antibiotic that is usually sufficient to
inhibit or kill organisms of the same species.
2. Antibiotic resistance is one of the biggest threats to global health, food
security, and development today.
3. Antibiotic resistance can affect anyone, of any age, in any country.
4. Antibiotic resistance occurs naturally, but misuse of antibiotics in humans and
animals is accelerating the process.
5. A growing number of infections – such as pneumonia, tuberculosis,
gonorrhoea, and salmonellosis – are becoming harder to treat as the
antibiotics used to treat them become less effective.
6. Antibiotic resistance leads to longer hospital stays, higher medical costs and
increased mortality.

41. 1
2

42. Some examples of
Antibiotic-resistant microbial infections
1. TB
2. MALARIA
3. GONORRHEA
4. HIV
5. STREP PNEUMONIA
6. SUPERFICIAL DERMATOPHYTES

43. DR-TB
• MDR- multi
• XDR- extensively
• ?TDR- total

44. TDR IS NOT ONLY SCARY..ITS REAL TOO..!!
*Source- Udwadia ZF, Amale RA, Ajbani KK, Rodrigues C. Totally drug-resistant tuberculosis in India. Clin Infect Dis. 2012 Feb 15;54(4):579-81. doi: 10.1093/cid/cir889. Epub 2011 Dec 21.

45. MALARIA

46. HIV
• Emergence of some HIVDR is inevitable due to
1. error-prone replication of HIV
2. high mutation rate
3. need for lifelong treatment
• Higher levels of HIVDR observed in areas with greater ART coverage
• In SEAR, amongst those with virological failure*--
Acquired NRTI resistance ranged from 52%–92%
Acquired NNRTI resistance ranged from 43%–100%
*Andrew B. Trotter,Steven Y. Hong,Padmini Srikantiah,Iyanthi Abeyewickreme,Silvia Bertagnolio,Michael R. Jordan. Systematic Review of HIV Drug Resistance in the World Health Organization Southeast Asia Region AIDS Rev. 2013 ; 15(3): 162–170.

47. Antibiotic resistance in Dermatology and STIs
1. Acne vulgaris and acne rosacea
2. Cellulitis and erysipelas
3. Folliculitis
4. MRSA
5. Impetigo and ecthyma
6. Necrotizing fasciitis and staphylococcal scalded skin syndrome
7. Cutaneous TB -lupus vulgaris and papulonecrotic tuberculids
8. Sexually transmitted diseases
a. Syphilis
b. Gonorrhea
c. Chlamydia
d. Chancroid

48. Antibiotic Resistance of Pathogens Causing
Community-Acquired Pneumonia
• Streptococcus pneumoniae (pneumococcus)

49. Antibiotic resistance in fungal infections
There are a limited number of antifungal drugs for the treatment of
invasive fungal infections, with the three main classes being azoles,
polyenes and echinocandins.
Intrinsic resistance of fungal pathogens is prevalent and acquired
resistance to available antifungals is on the rise.

50. NDM-1 or ?Superbug
Extended spectrum β-lactamase (ESBL)] producing Enterobacteriaceae led to increased
reliance on carbapenems for effective treatment of infection
A novel type of carbapenemase, New Delhi metallo beta-lactamase 1 (NDM 1), was first
identified in 2008 in two Enterobacteriacea isolates.
The emergence of NDM 1 is now reported from all continents, often in patients with a history
of travel or hospitalization in the Indian subcontinent.
Some isolates have developed resistance to practically all available antibiotics.
Environmental studies have shown different organisms harbouring NDM-1 (e.g. Shigella boydii
and Vibrio cholerae) suggesting transfer of mobile resistance elements between species
Meticillin resistance (MRSA) is seen in S. aureus

51. Mechanisms by which Cigarette Smoking Predisposes to Antibiotic
Treatment Failure and Resistance

62. Strategy for controlling emerging & reemerging infections
1. Cost-effective interventions like early diagnosis & treatment
2. Vector control measures
3. Timely & accurate reporting, sharing of information with authorities.
4. Exit screening of all international travellers.
5. Using suitable antibiotics in a suitable dose for required period of time.
6. Using the drugs in combinations to prevent secondary drug resistance.