Molecular characterization of antibiotic resistant bacteria in newly HIV diagnosed adults in a community setting in Tanzania. Implications for infection prevention and control in HIV : Antibiotic resistant bacteria, HIV, Community, Sub-Saharan Africa

Mennesker som lever med HIV-infeksjon i utviklingsland har økt risiko for å bli smittet med antibiotikaresistente bakterier. Høyere forbruk av antibiotika på grunn av HIV-relatert sykdom gir et seleksjonspress som kan føre til fremvekst av antibiotikaresistente bakterier. Bærerskap av antibiotikaresistente bakterier med virulensgener øker risikoen for alvorlige infeksjoner i denne populasjonen. Målet med avhandlingen var å anslå forekomsten av og karakterisere antibiotikaresistente bakterier som koloniserer voksne mennesker med nypåvist HIV-infeksjon i bydeler i Dar es Salaam, Tanzania. Resultatene av avhandlingen kan hjelpe å utvikle strategier for å forebygge og kontrollere spredning av, og infeksjoner med, antibiotikaresistente bakterier blant mennesker som lever med HIV. Penselprøver ble tatt fra rektum og fra nese og nasofarynks på voksne personer med nypåvist HIV-infeksjon og undersøkt for antibiotikaresistente bakterier, extended spectrum beta-lactamase produserende Enterobacterales (ESBLPE), karbapenemase-produserende Enterobacterales (CPE), meticillin-resistente Staphylococcus aureus (MRSA), og antibiotikaresistente pneumokokker (Streptococcus pneumoniae). Studien fant at bare 4% (22/537) av HIV-positive deltakere hadde MRSA i nese / nasofarynx. Disse MRSA-isolatene var ofte resistente mot gentamicin (95%), ciprofloksacin (91%) og erytromycin (82%), men sjeldnere resistente mot kotrimoksasol (9%). Vi fant at MRSA-isolatenes fenotypiske følsomhetsmønster stemte godt overens med funn av resistensgener og mutasjoner i bakteriene. Alle MRSA isolatene tilhørte CC8 og ST8-SCCmecIV MRSA klonene og var negative for panton-valentine leukocidin (PVL) og arginine catabolic mobile element (ACME) type 1. Ingen av ST8-SCCmecIV spa-t1476 MRSA klonene fra Tanzania var beslektet med den globalt spredde USA300 klonen. Studien viste at personer med nypåvist HIV-infeksjon hadde høy forekomst av rektalt bærerskap av ESBLPE (32.6%, 194/595), med overvekt av genotype CTX-M-15. Antibiotikabruk siste 4 uker og CD4 tall under 350 celler/μL var uavhengige risikofaktorer for fekalt bærerskap av ESBLPE. Vi fant karbapenemasen blaNDM-5 lokalisert på et IncX3 type plasmid i et E. coli ST2083 isolat fra rektalpensel fra en person med HIV-infeksjon. Isolatet hadde også 3 andre plasmider, IncFIA, IncFIB og Col(BS512). IncFA plasmidet bar gener som uttrykker resistens mot fluorokvinoloner, aminoglykosider, trimetoprim, sulfametoksazol, makrolider og tetrasykliner. Studien viste at pneumokokker fra nasofarynks på personer med HIV-infeksjon hadde høy forekomst av resistens mot penicillin (74%) og kotrimoksasol (71%), antibiotika som ofte brukes som behandling mot lungebetennelse i Tanzania. Videre var 26.3% av pneumokokkene multiresistente og kotrimoksasol-resistente pneumokokker hadde multiple mutasjoner i dihydrofolatreduktase genene. For å oppsummere fant vi at personer med nypåvist HIV-infeksjon i bydeler i Dar es Salaam ofte var bærere av antibiotikaresistente bakterier. Funnene setter søkelys på den store spredningen av antibiotikaresistente bakterier i Tanzania, ikke bare i sykehus, men også ute i samfunnet. Funn av E. coli med plasmidbårne karbapenemaser av type blaNDM-5 og flere andre resistensdeterminanter setter søkelys på behovet for å implementere intervensjoner for å hindre spredning av antibiotikaresistente bakterier.In developing countries human immunodeficiency virus infected individuals are at increased risk of acquiring antibiotic resistant bacteria. High frequency of antibiotic use associated with HIV related illness drives emergence of bacteria with antimicrobial resistance (AMR) due to selection pressure. The carriage of antibiotic resistant bacteria coupled with virulence genes increases the risk of severe infections in this population. The aim of this thesis was detection and characterization of antibiotic-resistant bacteria colonizing newly HIV diagnosed adults in a community setting in Tanzania. The findings could help in developing strategies for preventing and controlling the spread and infection of antibiotic resistant bacteria in HIV-positive individuals. Rectal and nasal/nasopharyngeal swabs collected from newly HIV diagnosed adults from the community were used for detection of antibiotic resistant bacteria including extended spectrum b-lactamase producing Enterobacterales (ESBLPE), carbapenemase producing Enterobacterales (CPE), methicillin-resistant Staphylococcus aureus (MRSA), and antibiotic-resistant Streptococcus pneumoniae. The study found that only 4% (22/537) of the HIV-positive participants carried MRSA in the nose/nasopharynx. These MRSA isolates were frequently resistant to gentamicin (95%), ciprofloxacin (91%), and erythromycin (82%), but less often to trimethoprim-sulfamethoxazole (9%). We found that the phenotypic susceptibility patterns of all MRSA isolates were highly concordant with genotypic findings (resistance genes and mutations in genome). All MRSA isolates belonged to the CC8 and ST8-SCCmecIV MRSA clone and negative for panton-valentine leukocidin (PVL) and arginine catabolic mobile element (ACME) type 1. All ST8-SCCmecIVspa-t1476 MRSA clones from Tanzania were unrelated to the globally successful USA300 clone. The study showed a high prevalence (32.6%, 194/595) of fecal carriage of ESBL-PE in newly HIV diagnosed adults in the community setting, and confirmed the predominance of the blaCTX-M-15 genotype. Antibiotic use in the last 4 weeks and CD4 count <350 cells/μL were independent risk factors for fecal carriage of ESBL-PE in this HIV-infected population. In this study, we detected blaNDM-5 carried on an IncX3 type plasmid in one E. coli ST2083 isolate obtained from an HIV-infected adult from the community setting in Tanzania. In addition, E. coli from the HIV-infected adult carried three more plasmid types; IncFIA, IncFIB and Col(BS512). The IncFA type plasmid was found to carry several genes conferring resistance against fluoroquinolone, aminoglycosides, sulfamethoxazole, trimethoprim, macrolides and tetracycline. The study found that Streptococcus pneumoniae colonizing the nasopharynx of HIV-infected adults displayed a high rate of resistance to penicillin (74%) and cotrimoxazole (71%), antibiotics commonly used as first line treatment in suspected bacterial pneumonia in Tanzania. Furthermore, 26.3% were multidrug-resistance (MDR) and cotrimoxazole-resistant Streptococcus pneumoniae had multiple mutations in the dihydrofolate reductase gene. In conclusion, we found that carriage of antibiotic resistant bacteria was common among newly diagnosed HIV-infected adults from community settings. This highlights the large-scale spread of these resistant bacteria in Tanzania, not only in hospitals, but also in the community as well. The detection of a blaNDM-5 producing E. coli carried on a plasmid with clusters of other resistance determinant genes calls for urgent implementation of intervention strategies to curb the spread of antimicrobial resistant bacteria.Doktorgradsavhandlin

Bacteriological Spectrum of Post Operative Wound Infections and their Antibiogram in a Tertiary Hospital, Dar es salaam, Tanzania

Surgical site infection (SSI) is among the most common problem for patients who undergo operative procedures. It remains a common and widespread problem contributing to morbidity and mortality; partly attributed to increase in infections due to antimicrobial resistant bacterial pathogens. In Tanzania there has been limited data regarding the magnitude of SSIs due to antimicrobial resistant pathogens as well as the resistant pattern to antibiotics commonly used in the treatment of these infections. To determine the spectrum of bacteria isolates from postoperative wound infections and their antimicrobial susceptibility patterns at Muhimbili National Hospital (MNH) and Muhimbili Orthopedic Institute (MOI). This was a descriptive cross sectional study which was conducted among patients with post operative wound infections in the general surgery and obstetrics/gynecology wards at MNH and Orthopedics and Trauma unit at MOI. The study participants were consecutively recruited in general surgery, obstetrics/gynecology wards at MNH and orthopedics and trauma wards at MOI from September 2011 to February, 2012. Structured questionnaires were used to collect social demographic characteristics, clinical history and operative information from patients and their case notes. Culturing for colony characteristics followed by Gram stain was used for provisional identity of pathogenic bacteria. Further identification was done by a set of biochemical tests, API 20E, and VITEK. Antimicrobial susceptibility pattern of isolated bacterial pathogens was determined by Kirby Bauer disc diffusion method. Pseudomonas aeruginosa was the most frequently isolated pathogenic organism from post operative wound infections. Most of the Gram negative bacteria isolated were multiply resistant to antimicrobial agents tested; but all were sensitive to carbapenems. Eighty eight percent (88%) of enteric gram negative rods were multi-drug resistance. ESBLs production viii was detected in 92.3% of Escherichia coli and 69% of Klebsiella pneumoniae. Forty four percent (44%) of the 18 S. aureus isolates obtained were MRSA. Pseudomonas aeruginosa was the most common isolate from SSI. Most of gram negative isolates were multiply resistant to commonly prescribed antimicrobial agents. Also there was an increase in ESBLs producing Enterobacteriaceae as well as MRSA strains. Routine culture should be performed whenever SSI is suspected and choice of antibiotics for treatment of SSIs should be guided by routine antimicrobial sensitivity (including MRSA and ESBL screening) testing. Ciprofloxacin should replace first line antibiotics for empirical treatment of SSIs; and strict guidelines for antibiotics prescriptions in treatment of SSIs should be established

Student Challenges in Understanding Quantum Mechanics: Effect of the “Logic paradigm shift”

For three centuries Newtonian mechanics had been firmly established as a valid theory for the understanding of physical reality; if one understands the laws of physics, then one understands the whole universe. Classical physicists had contented themselves with the search for regularities in measurements and in the physical world.  Irregularities were regarded as noises that interfered with the deterministic picture of physical reality. However, from 1900s onwards with the quantum hypothesis, physicists had begun to recognize that the physics of Newton and Maxwell were inadequate for the understanding of all of the physical reality. For example, the interaction of radiation with matter could not be explained from classical physics. This dilemma led to the discovery of quantum mechanics. In this article we explore the challenges that students face in understanding quantum mechanics that arises from paradigm shift in the mode of reasoning about the physical world. The description of physical reality in general and quantum reality in particular requires that we shift our mode of reasoning from classical Boolean logic to quantum non Boolean logic

Genetic determinants of macrolide and tetracycline resistance in penicillin non-susceptible Streptococcus pneumoniae isolates from people living with HIV in Dar es Salaam, Tanzania

Background: Over one million yearly deaths are attributable to Streptococcus pneumoniae and people living with HIV are particularly vulnerable. Emerging penicillin non-susceptible Streptococcus pneumoniae (PNSP) challenges therapy of pneumococcal disease. The aim of this study was to determine the mechanisms of antibiotic resistance among PNSP isolates by next generation sequencing. Methods: We assessed 26 PNSP isolates obtained from the nasopharynx from 537 healthy human immunodeficiency virus (HIV) infected adults in Dar es Salaam, Tanzania, participating in the randomized clinical trial CoTrimResist (ClinicalTrials.gov identifier: NCT03087890, registered on 23rd March, 2017). Next generation whole genome sequencing on the Illumina platform was used to identify mechanisms of resistance to antibiotics among PNSP. Results: Fifty percent (13/26) of PNSP were resistant to erythromycin, of these 54% (7/13) and 46% (6/13) had MLSB phenotype and M phenotype respectively. All erythromycin resistant PNSP carried macrolide resistance genes; six isolates had mef(A)-msr(D), five isolates had both erm(B) and mef(A)-msr(D) while two isolates carried erm(B) alone. Isolates harboring the erm(B) gene had increased MIC (> 256 µg/mL) towards macrolides, compared to isolates without erm(B) gene (MIC 4-12 µg/mL) p < 0.001. Using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines, the prevalence of azithromycin resistance was overestimated compared to genetic correlates. Tetracycline resistance was detected in 13/26 (50%) of PNSP and all the 13 isolates harbored the tet(M) gene. All isolates carrying the tet(M) gene and 11/13 isolates with macrolide resistance genes were associated with the mobile genetic element Tn6009 transposon family. Of 26 PNSP isolates, serotype 3 was the most common (6/26), and sequence type ST271 accounted for 15% (4/26). Serotypes 3 and 19 displayed high-level macrolide resistance and frequently carried both macrolide and tetracycline resistance genes. Conclusion: The erm(B) and mef(A)-msr(D) were common genes conferring resistance to MLSB in PNSP. Resistance to tetracycline was conferred by the tet(M) gene. Resistance genes were associated with the Tn6009 transposon.publishedVersio

High rate of antimicrobial resistance and multiple mutations in the dihydrofolate reductase gene among Streptococcus pneumoniae isolated from HIV-infected adults in a community setting in Tanzania

Objectives The aim of this study was to characterize molecular mechanisms of resistance to trimethoprim and other antibiotics in Streptococcus pneumoniae isolates from HIV-infected adults in Dar es Salaam, Tanzania. Methods A total of 1877 nasopharyngeal swabs were collected and screened for pneumococcal colonization from 537 newly diagnosed individuals with HIV at four clinic visits during a 1-year follow-up from 2017–2018 as part of the randomized clinical trial CoTrimResist (ClinicalTrials.gov ID: NCT03087890). Results A total of 76 pneumococcal isolates were obtained. Of the 70 isolates that could be serotyped, 42 (60.0%) were vaccine serotypes included in pneumococcal conjugate vaccine 23 (PCV23). The majority of isolates (73.7%; 56/76) were non-susceptible to penicillin (MICs of 0.06–2 μg/mL). Isolates were frequently resistant to co-trimoxazole (trimethoprim/sulfamethoxazole) (71.1%) but less so to azithromycin (22.4%), erythromycin (21.1%), chloramphenicol (18.4%), tetracycline (14.5%), clindamycin (10.5%) and levofloxacin (0%). Moreover, 26.3% were multidrug-resistant (resistant to ≥3 antibiotic classes). Vaccine-type pneumococci were resistant to more classes of antibiotics, were more frequently resistant to erythromycin, azithromycin, clindamycin and tetracycline, and had higher MICs to penicillin (median, 0.19 μg/mL; range, 0.002–1.5 μg/mL) compared with non-vaccine serotypes (median, 0.125 μg/mL; range, 0.012–0.25 μg/mL) (P = 0.003). Co-trimoxazole-resistant isolates carried from 1 to 11 different mutations in the dihydrofolate reductase (DHFR) gene, most commonly Ile100Leu (100%), Glu20Asp (91.8%), Glu94Asp (61.2%), Leu135Phe (57.1%), His26Tyr (53.1%), Asp92Ala (53.1%) and His120Gln (53.1%). Conclusion Streptococcus pneumoniae isolated from HIV-diagnosed patients were frequently non-susceptible to penicillin and co-trimoxazole. Most isolates carried multiple mutations in DHFR.publishedVersio

Predominance of PVL-negative community-associated methicillin-resistant Staphylococcus aureus sequence type 8 in newly diagnosed HIV-infected adults, Tanzania

Difficult-to-treat infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are of concern in people living with HIV infection as they are more vulnerable to infection. We aimed to identify molecular characteristics of MRSA colonizing newly diagnosed HIV-infected adults in Tanzania. Individuals newly diagnosed with HIV infection were recruited in Dar es Salaam, Tanzania, from April 2017 to May 2018, as part of the randomized clinical trial CoTrimResist (ClinicalTrials.gov identifier: NCT03087890). Nasal/nasopharyngeal isolates of Staphylococcus aureus were susceptibility tested by disk diffusion method, and cefoxitin-resistant isolates were characterized by short-reads whole genome sequencing. Four percent (22/537) of patients carried MRSA in the nose/nasopharynx. MRSA isolates were frequently resistant towards gentamicin (95%), ciprofloxacin (91%), and erythromycin (82%) but less often towards trimethoprim-sulfamethoxazole (9%). Seventy-three percent had inducible clindamycin resistance. Erythromycin-resistant isolates harbored ermC (15/18) and LmrS (3/18) resistance genes. Ciprofloxacin resistance was mediated by mutations of the quinolone resistance-determining region (QRDR) sequence in the gyrA (S84L) and parC (S80Y) genes. All isolates belonged to the CC8 and ST8-SCCmecIV MRSA clone. Ninety-five percent of the MRSA isolates were spa-type t1476, and one exhibited spa-type t064. All isolates were negative for Panton-Valentine leucocidin (PVL) and arginine catabolic mobile element (ACME) type 1. All ST8-SCCmecIV-spa-t1476 MRSA clones from Tanzania were unrelated to the globally successful USA300 clone. Carriage of ST8 MRSA (non-USA300) was common among newly diagnosed HIV-infected adults in Tanzania. Frequent co-resistance to non-beta lactam antibiotics limits therapeutic options when infection occurs.publishedVersio

High prevalence of fecal carriage of extended spectrum β-lactamase-producing enterobacteriaceae among newly HIV-diagnosed adults in a community setting in Tanzania

Colonization in HIV-infected populations with extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) is particularly worrisome in low-income settings. This study describes the prevalence of ESBL-PE carriage and associated risk factors among newly HIV-diagnosed adults in a community setting in Tanzania. A total of 595 newly diagnosed HIV-positive adults with a median age of 35 years with interquartile range (IQR) 29–42 years and a median CD4 count of 492 cells/μL (IQR 390–666 cells/μL) were recruited. Among these, 194/595 (32.6%, 95% confidence interval [CI] 28.9–36.6) were ESBL-PE carriers. Participants with low CD4 count (<350 cells/μL) had significantly higher prevalence of ESBL-PE carriage compared with those with CD4 count ≥350 cells/μL (26/58, 44.8%, vs. 168/537, 31.3%, p = 0.04). Antibiotic use in last 4 weeks (odds ratio [OR] 1.55, 95% CI 1.08–2.22, p = 0.02) and CD4 count <350 cells/μL (OR 1.78, 95% CI 1.03–3.09, p = 0.04) were independent risk factors for fecal carriage of ESBL-PE. In total, 244 isolates of ESBL-PE were isolated from 194 participants. Of these, 238/244 (97.5%) harbored blaCTX-M genes, with blaCTX-M-15 being predominant (219/238 (92%), followed by blaCTX-M-27 (9/238 (3.8%), blaCTX-M-14 (8/238 (3.4%), blaCTX-M-55 (1/238), and blaCTX-M 211/3 (1/238). blaSHV-2a genes were detected in four isolates, whereas the blaSHV-12 gene was detected in one isolate. Phenotypic carbapenemase-producing Enterobacteriaceae was detected in one HIV-positive person with CD4 count 132 cells/μL. In conclusion prevalence of ESBL-PE carriage is high among newly diagnosed HIV adults in Dar es Salaam, and is significantly associated antibiotic use and low CD4 count.publishedVersio

Seroprevalence and risk factors of Toxoplasmosis among HIV infected women of child-bearing age attending care and treatment clinics in Dar es Salaam, Tanzania

Background: Toxoplasmosis in HIV-infected women of child-bearing age (HIV-WCB) increases the risk for congenital toxoplasmosis, leading to many complications. However, its magnitude is unknown in this population. Objectives: The study aimed to determine the prevalence and factors associated with toxoplasmosis among HIV-WCB. Methods: This was a cross-sectional study conducted from July to August 2020 among HIV- WCB attending care and treatment clinic (CTC) at Muhimbili National Hospital and Mnazi Mmoja hospital. Questionnaire and TORCH rapid test were used to obtain data and serological testing respectively. Data analysis was done using statistical package for social sciences (SPSS) version 20. Results: Overall, 29.7% of the study participants were positive for anti-T. gondii IgG, whereas none tested positive for IgM. Multivariate analysis showed that the probability of being infected with T. gondii increased by 57.1% for participants who consumed raw vegetables (p=0.005, aOR=0.43, 95%CI = 1.24-8.77). Other common risk factors such as undercooked meat consumption, source of drinking water, and cat ownership at home showed no association. Conclusion: A high number of HIV-WCB have not developed immunity to T. gondii in the study area. Introduction of routine screening during antenatal visits for pregnant women and further epidemiological studies are warranted in the country. Keywords: T. gondii; HIV women

Pediatric HIV care and treatment services in Tanzania: implications for survival.

BACKGROUND: Improving child survival for HIV-infected children remains an important health agenda. We present progress regarding care and treatment services to HIV infected children in Tanzania. METHODS: The National AIDS Control Programme Care and Treatment (CTC 2) database was used to obtain information of all children aged 0-14yearsenrolled in the HIV Care and Treatment Program between January 2011 and December 2014. We assessed eligibility for ART, time from enrolment to ART initiation, nutritional status, and mortality using Kaplan-Meier methods. RESULTS: A total of 29,531 (14,304 boys and 15,227 girls) ART-naive children aged 0-14 years were enrolled during the period, approximately 6700 to 8000 children per year. The male to female ratio was 48:50. At enrolment 72% were eligible for ART, 2-3% of children were positive for TB, and 2-4% were severely malnourished. Between 2011 and 2014, 2368 (8%) died, 9243 (31%) were Lost to Follow-up and 17,920 (61%) were on care or ART. The probability of death was 31% (95% CI 26-35), 43% (40-47), 52% (49-55) and 61% (58-64) by 1,2, 5 and 10 years of age, respectively. The hazard of death was greatest at very young ages (<2 years old), and decreased sharply by 4 years old. Children who were on ART had around 10-15% higher survival over time. CONCLUSIONS: Significant progress has been made regarding provision of paediatric HIV care and treatment in Tanzania. On average 7000 children are enrolled annually, and that approximately two thirds of children diagnosed under the age of 2 years were initiated on ART within a month. Provision of ART as soon as the child is diagnosed is the biggest factor in improving survival. However we noted that i) most children had advanced disease at the time of enrolment ii) approximately two-thirds of children were missing a baseline CD4 measurement and only 35% of children had either a CD4 count or percentage recorded, indicating limited access to CD4 testing services, and iii) 31% were lost to follow-up (LTFU). These challenges need to be addressed to improve early detection, enrolment and retention of HIV-infected children into care and improve documentation of services offered

Bacteraemia, Malaria, and Case Fatality Among Children Hospitalized With Fever in Dar es Salaam, Tanzania

Background Febrile illness is the commonest cause of hospitalization in children <5 years in sub-Saharan Africa, and bacterial blood stream-infections and malaria are major causes of death. Methods From March 2017 to July 2018, we enrolled 2226 children aged 0-5 years hospitalized due to fever in four major public hospitals of Dar es Salaam namely; Amana, Temeke and Mwananyamala Regional Hospitals and Muhimbili National Hospital. We recorded social demographic and clinical data, performed blood-culture and HIV-antibody testing. We used qPCR to quantify Plasmodium falciparum parasitaemia and Matrix-Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) to identify bacterial isolates. Disk diffusion method was used for antimicrobial susceptibility testing. Results Nineteen percent of the children (426/2226) had pathogens detected from blood. Eleven percent (236/2226) of the children had bacteraemia/fungaemia and 10% (204/2063) had P. falciparum malaria. Ten children had concomitant malaria and bacteraemia. Gram-negative bacteria (64%) were more frequent than Gram-positive (32%) and fungi (4%). Over fifty percent of Gram-negative bacteria were extended-spectrum beta-lactamase (ESBL) producers and multidrug resistant. Methicillin resistant Staphylococcus aureus (MRSA) was found in 11/42 (26.2%). The most severe form of clinical malaria was associated with high parasitaemia (>four million genomes/µL) of P. falciparaum in plasma. Overall, in-hospital death was 4% (89/2146) and it was higher in children with bacteraemia (8%, 18/227) than malaria (2%, 4/194, P=0.007). Risk factors for death were bacteraemia (p=0.03), unconsciousness at admission (p<0.001) and admission at a tertiary hospital (p=0.003). Conclusions Compared to previous studies in this region, our study showed a reduction in malaria prevalence, a decrease in in-hospital mortality and an increase in antimicrobial resistance (AMR) including ESBLs and multidrug resistance. An increase of AMR highlights the importance of continued strengthening of diagnostic capability and antimicrobial stewardship programs. We also found malaria and bacteraemia contributed equally in causing febrile illness but bacteraemia caused higher in-hospital death. The most severe form of clinical malaria was associated with P. falciparum parasitaemia