# CDC catch-up immunization interval (ACIP)

CDC catch-up immunization interval (ACIP)

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/cdc_imm`
HTML: https://magentlab.com/docs/cdc-imm
Markdown: https://magentlab.com/docs/cdc-imm.md

Not a medical device. Not a diagnosis, dose, or listing recommendation.

## What it computes

Return the printed ACIP 2025 catch-up Table 2 minimum age and previous-dose interval for a caller-assigned antigen and dose, and whether that age and interval are met.

## When to use

When an agent already has a caller-assigned antigen, dose number, completed age in months, and weeks since the previous dose (omitted for dose 1) and needs the numeric catch-up Table 2 cell rather than the routine age bars or a vaccine order.

## When not to use

- Not a medical device. Not a vaccine order. magent does not immunize.
- Catch-up Table 2 numeric minimum age and previous-dose interval cells only. Not the full routine schedule (Table 1) and not Table 3 medical-indication rows.
- HepB dose 3 (8 weeks and 16 weeks after dose 1), Hib, PCV, rotavirus max ages, 6-month intervals, the 4-day grace period, and live-virus spacing beyond this table are not implemented.
- DTaP is the 4-month-through-6-year section (age_months < 84). 6 weeks is stored as 1.5 months. Age is caller-assigned completed months; magent does not derive chronological age.

## Formula

```
ACIP 2025 child/adolescent catch-up Table 2: eligible if age_months >= minimum_age_months and (dose 1 has no printed interval, or weeks_since_previous_dose >= minimum_interval_weeks). HepB dose 1 birth = 0 months; HepB dose 2 = 4 weeks. MMR dose 1 = 12 months; MMR dose 2 = 4 weeks. HepA and varicella dose 1 = 12 months. DTaP/IPV dose 1 = 6 weeks as 1.5 months; DTaP doses 2-3 and IPV dose 2 = 4 weeks (DTaP only when age_months < 84). Tdap dose 1 = 84 months. Not Table 1 routine bars. Not Hib, PCV, rotavirus, HepB dose 3, 6-month intervals, the 4-day grace period, or live-virus spacing beyond this table. magent does not immunize
```

## Citation

[Advisory Committee on Immunization Practices Recommended Immunization Schedule for Children and Adolescents Aged 18 Years or Younger — United States, 2025](https://doi.org/10.15585/mmwr.mm7402a2)
Issa AN, Wodi AP, Moser CA, Cineas S
MMWR Morb Mortal Wkly Rep. 2025;74(2):26-29
DOI: [10.15585/mmwr.mm7402a2](https://doi.org/10.15585/mmwr.mm7402a2)

## Worked example

### HepB dose 2 at 4 months, 4 weeks after dose 1: eligible

Given: `age_months=4, dose_number=2, vaccine=hepb, weeks_since_previous_dose=4`

1. Table 2 Hepatitis B dose 1 to dose 2 minimum interval is 4 weeks
2. Minimum age for HepB dose 1 is birth (0 months); age 4 months meets it
3. weeks_since_previous_dose 4 >= 4 → eligible true


### HepB dose 2 at 4 months, 3 weeks after dose 1: too soon

Given: `age_months=4, dose_number=2, vaccine=hepb, weeks_since_previous_dose=3`

1. Table 2 Hepatitis B dose 1 to dose 2 minimum interval is 4 weeks
2. Age 4 months meets the birth minimum
3. weeks_since_previous_dose 3 < 4 → eligible false


### HepB dose 1 at 4 months: no previous-dose interval

Given: `age_months=4, dose_number=1, vaccine=hepb`

1. Table 2 Hepatitis B dose 1 minimum age is birth (0 months)
2. Dose 1 has no printed previous-dose interval
3. age 4 months >= 0 and interval not applicable → eligible true


## Also searched as

- CDC catch-up immunization
- ACIP catch-up schedule
- hepatitis B minimum interval
- MMR minimum age
- catch-up vaccine interval
- Table 2 catch-up

## Parameters

- `vaccine` (string, required): Caller-assigned antigen with a numeric Table 2 minimum age and/or previous-dose interval: hepb, mmr, dtap, ipv, hepa, var, or tdap. Not a vaccine order.
- `dose_number` (integer, required): Dose number in the series as printed (integer 1-5). Only rows with a numeric minimum age and/or interval are implemented; other dose numbers are rejected.
- `age_months` (integer, required): Caller-assigned completed age in months (integer 0-216; 18 years or younger). magent does not derive chronological age.
- `weeks_since_previous_dose` (integer, optional): Whole weeks since the previous dose (integer 0-520). Required for dose 2 and later. Must be omitted for dose 1 as Table 2 prints no previous-dose interval.

## Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

Method: `POST /api/calc/cdc_imm`
Max items: 25
Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic)
Status: PREVIEW

- 1 to 25 items. Each item uses the same keys as the GET query parameters.
- POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
- The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
- HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
- Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
- x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request:

```json
{
  "items": [
    {
      "age_months": "4",
      "dose_number": "2",
      "vaccine": "hepb",
      "weeks_since_previous_dose": "4"
    },
    {
      "age_months": "4",
      "dose_number": "2",
      "vaccine": "hepb",
      "weeks_since_previous_dose": "4"
    }
  ]
}
```

Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/cdc-imm

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/cdc_imm",
  "items": [
    {
      "components": [
        {
          "value": 0,
          "factor": "age_met",
          "met": true
        },
        {
          "value": 4,
          "factor": "interval_met",
          "met": true
        }
      ],
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Issa AN, Wodi AP, Moser CA, Cineas S",
        "doi": "10.15585/mmwr.mm7402a2",
        "id": "cdc-acip-catch-up-schedule",
        "pmid": "39819853",
        "source": "MMWR Morb Mortal Wkly Rep. 2025;74(2):26-29",
        "title": "Advisory Committee on Immunization Practices Recommended Immunization Schedule for Children and Adolescents Aged 18 Years or Younger — United States, 2025"
      },
      "formula": "cdc_imm",
      "formula_expression": "ACIP 2025 child/adolescent catch-up Table 2: eligible if age_months >= minimum_age_months and (dose 1 has no printed interval, or weeks_since_previous_dose >= minimum_interval_weeks). HepB dose 1 birth = 0 months; HepB dose 2 = 4 weeks. MMR dose 1 = 12 months; MMR dose 2 = 4 weeks. HepA and varicella dose 1 = 12 months. DTaP/IPV dose 1 = 6 weeks as 1.5 months; DTaP doses 2-3 and IPV dose 2 = 4 weeks (DTaP only when age_months < 84). Tdap dose 1 = 84 months. Not Table 1 routine bars. Not Hib, PCV, rotavirus, HepB dose 3, 6-month intervals, the 4-day grace period, or live-virus spacing beyond this table. magent does not immunize",
      "age_months": 4,
      "dose_number": 2,
      "eligible": true,
      "minimum_age_months": 0,
      "minimum_interval_weeks": 4,
      "vaccine": "hepb",
      "weeks_since_previous_dose": 4
    },
    {
      "components": [
        {
          "value": 0,
          "factor": "age_met",
          "met": true
        },
        {
          "value": 4,
          "factor": "interval_met",
          "met": true
        }
      ],
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Issa AN, Wodi AP, Moser CA, Cineas S",
        "doi": "10.15585/mmwr.mm7402a2",
        "id": "cdc-acip-catch-up-schedule",
        "pmid": "39819853",
        "source": "MMWR Morb Mortal Wkly Rep. 2025;74(2):26-29",
        "title": "Advisory Committee on Immunization Practices Recommended Immunization Schedule for Children and Adolescents Aged 18 Years or Younger — United States, 2025"
      },
      "formula": "cdc_imm",
      "formula_expression": "ACIP 2025 child/adolescent catch-up Table 2: eligible if age_months >= minimum_age_months and (dose 1 has no printed interval, or weeks_since_previous_dose >= minimum_interval_weeks). HepB dose 1 birth = 0 months; HepB dose 2 = 4 weeks. MMR dose 1 = 12 months; MMR dose 2 = 4 weeks. HepA and varicella dose 1 = 12 months. DTaP/IPV dose 1 = 6 weeks as 1.5 months; DTaP doses 2-3 and IPV dose 2 = 4 weeks (DTaP only when age_months < 84). Tdap dose 1 = 84 months. Not Table 1 routine bars. Not Hib, PCV, rotavirus, HepB dose 3, 6-month intervals, the 4-day grace period, or live-virus spacing beyond this table. magent does not immunize",
      "age_months": 4,
      "dose_number": 2,
      "eligible": true,
      "minimum_age_months": 0,
      "minimum_interval_weeks": 4,
      "vaccine": "hepb",
      "weeks_since_previous_dose": 4
    }
  ]
}
```

## Response fields

- `formula` (string): cdc_imm
- `formula_expression` (string): Published ACIP 2025 Table 2 catch-up age and interval rule
- `vaccine` (string): Caller-assigned antigen used
- `dose_number` (integer): Dose number in the series
- `age_months` (integer): Caller-assigned completed age in months
- `weeks_since_previous_dose` (integer): Weeks since the previous dose, or null for dose 1
- `minimum_age_months` (number): Printed minimum age in months for that antigen and dose
- `minimum_interval_weeks` (integer): Printed previous-dose interval in weeks, or null for dose 1
- `eligible` (boolean): True when age meets the printed minimum and a printed interval is met. Not a vaccine order.
- `components` (array): Tree rows for age_met and interval_met with factor, met, and value
- `citation` (object): Issa 2025 MMWR ACIP schedule citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "components": [
    {
      "value": 0,
      "factor": "age_met",
      "met": true
    },
    {
      "value": 4,
      "factor": "interval_met",
      "met": true
    }
  ],
  "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "citation": {
    "authors": "Issa AN, Wodi AP, Moser CA, Cineas S",
    "doi": "10.15585/mmwr.mm7402a2",
    "id": "cdc-acip-catch-up-schedule",
    "pmid": "39819853",
    "source": "MMWR Morb Mortal Wkly Rep. 2025;74(2):26-29",
    "title": "Advisory Committee on Immunization Practices Recommended Immunization Schedule for Children and Adolescents Aged 18 Years or Younger — United States, 2025"
  },
  "formula": "cdc_imm",
  "formula_expression": "ACIP 2025 child/adolescent catch-up Table 2: eligible if age_months >= minimum_age_months and (dose 1 has no printed interval, or weeks_since_previous_dose >= minimum_interval_weeks). HepB dose 1 birth = 0 months; HepB dose 2 = 4 weeks. MMR dose 1 = 12 months; MMR dose 2 = 4 weeks. HepA and varicella dose 1 = 12 months. DTaP/IPV dose 1 = 6 weeks as 1.5 months; DTaP doses 2-3 and IPV dose 2 = 4 weeks (DTaP only when age_months < 84). Tdap dose 1 = 84 months. Not Table 1 routine bars. Not Hib, PCV, rotavirus, HepB dose 3, 6-month intervals, the 4-day grace period, or live-virus spacing beyond this table. magent does not immunize",
  "age_months": 4,
  "dose_number": 2,
  "eligible": true,
  "minimum_age_months": 0,
  "minimum_interval_weeks": 4,
  "vaccine": "hepb",
  "weeks_since_previous_dose": 4
}
```

## Errors

- HTTP 400 `invalid_cdc_imm`: CDC catch-up immunization inputs must match the printed vaccine, dose number, age, and interval columns. Returned before settlement; you are not charged.
- HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
- HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
- HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged.

Shared HTTP 402 and 503: https://magentlab.com/docs/payments

## Related tools

- [RhIG vials](https://magentlab.com/docs/rhig) — Compute ACOG Practice Bulletin 181 RhD immune globulin vial count from caller-assigned fetal-cell percent and maternal blood volume using AABB Technical Manual rounding of FMH/30.

## Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s.

- GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall).
- HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote.
- Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering.
- Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional.
- Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402.

- offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront.
- offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization.

- not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search.

Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers).

Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments

Stdio MCP (one process per host): https://magentlab.com/docs/mcp

## Guarantees

- HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
- exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
- HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
- Execution is timeout-bounded and concurrency-capped.
- Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.